ContourPlot class resource descriptions

Specifies the id of a ScalarField data object. There is no default for this resource; it the only resource that must be set in order for the ContourPlot object to draw a plot. You may create a ContourPlot object without setting the cnScalarFieldData, and auxiliary annotations such as tickmarks and titles may appear as the result of a draw, but the ContourPlot itself will not show up. The ScalarField object can provide either regularly spaced or irregular rectangular gridded data to the ContourPlot object, and provides a number of resources for controlling the ingestion of the raw data.

Default: <None>

cnLevelSelectionMode

This enumerated resource of type NhlcnLevelSelectionMode provides four methods for selecting the contour intervals displayed in a plot:

AutomaticLevels

Ordinarily this mode determines contour levels by picking a spacing value from a set of relatively "round" numbers scaled by powers of 10 to the range of the data. This set of numbers is as follows: 1.0, 2.0, 2.5, 4.0, 5.0. The number of levels chosen will be as close as possible to the value of cnMaxLevelCount without exceeding it. Once the spacing is chosen, the minimum contour level is set to the value of the least multiple of the spacing greater than the minimum data value. Likewise the maximum contour level becomes the greatest multiple of the spacing less than the maximum data value. Based on these values, ContourPlot set the resources cnLevelSpacingF, cnMinLevelValF, and cnMaxLevelValF appropriately.

On the other hand, if you explicitly set the resource cnLevelSpacingF to a valid value greater than 0.0 and less than the range of the data, it will be used as the interval spacing. The minimum and maximum levels are calculated as before. If as a consequence, cnMaxLevelCount is less than the number of levels so specified, it will be set to the number of levels actually needed. However, if the choice of spacing cause the absolute maximum number of levels, currently 256, to be exceeded ContourPlot will issue a warning message and recalculate the spacing as previously described.

In any case, ContourPlot sets the elements of the array resource cnLevels to the values of the contour levels chosen and the read-only resource cnLevelCount to the number of levels.

ManualLevels

ManualLevels mode bases the choice of contour levels on the values of the resources cnLevelSpacingF, cnMinLevelValF, and cnMaxLevelValF. Starting at cnMinLevelValF, contour levels are created at intervals spaced by the value of cnLevelSpacingF until cnMaxLevelValF is reached. The final contour level will always be cnMaxLevelValF. ContourPlot sets elements of the array resource cnLevels to the values of each contour level chosen and the read-only resource cnLevelCount to the number of levels. If the current value of cnMaxLevelCount is less than cnLevelCount it is reset to the value of cnLevelCount. However, if the level count would exceed the absolute maximum number of levels, currently 256, ContourPlot issues a warning and chooses a new value of cnLevelSpacingF based on the value of cnMaxLevelCount.

If you choose ManualLevels selection mode when the ContourPlot object is created, and do not set cnMinLevelValF ContourPlot will choose levels as if you had set AutomaticLevels mode. If you set cnMinLevelValF only, a default spacing is used, and the value of cnMaxLevelValF determined as it would be for AutomaticLevels mode.

ExplicitLevels

This mode allows you to specify the value of each contour level by explicitly setting the contents of the cnLevels array. If you choose ExplicitLevels selection mode when creating a ContourPlot object, but do not specify the contents of the cnLevels array, ContourPlot will choose levels as if you had specified AutomaticLevels mode. Thereafter, when you set ExplicitLevels mode, ContourPlot uses the current contents of cnLevels, whether or not you set it explicitly.

If the number of elements in cnLevels exceeds the absolute maximum number of levels (currently 256), ContourPlot issues a warning and the mode defaults to AutomaticLevels. Note that ContourPlot always sorts the elements of cnLevels into a monotonically increasing sequence. After sorting, cnMinLevelValF is set equal to the value of first element of cnLevels and cnMaxLevelValF is set to the value of the last element. cnLevelSpacingF is set to the average value of the spacing separating each level.

EqualSpacedLevels

For this mode, ContourPlot divides the range spanning the dataset minimum and maximum values into cnMaxLevelCount + 1 equally spaced intervals. cnLevelSpacingF is set to the value of this interval. cnMinLevelValF is set to the value of the dataset minimum plus the value of cnLevelSpacingF. cnMaxLevelSpacingF is set to the value of the dataset maximum minus the value of cnLevelSpacingF. This results in cnMaxLevelCount levels; therefore ContourPlot sets the read-only resource cnLevelCount equal to cnMaxLevelCount.

Default: AutomaticLevels

cnLevelCount

A read-only resource set to the actual number of levels chosen during the level selection process.

Default: <dynamic>

cnMaxLevelCount

When the cnLevelSelectionMode is AutomaticLevels and cnLevelSpacingF is not explicitly set ContourPlot picks a number of levels less than or equal to the current value of cnMaxLevelCount. If the cnLevelSelectionMode is EqualSpacedLevels ContourPlot picks exactly cnMaxLevelCount levels. If cnMaxLevelCount exceeds the absolute maximum level count allowed by ContourPlot (currently 256), a warning is issued and the value is reset to this maximum. If cnLevelSelectionMode is ManualLevels or ExplicitLevels or AutomaticLevels with cnLevelSpacingF explicitly set, ContourPlot sets cnMaxLevelCount to the number of levels actually used if this number is greater than the current value of cnMaxLevelCount.

Default: 16

cnLevelSpacingF

When the cnLevelSelectionMode is ManualLevels or when the cnLevelSelectionMode is AutomaticLevels, and cnLevelSpacingF is explicitly set, cnLevelSpacingF determines the spacing between contour intervals. Otherwise, the ContourPlot object sets the value of cnLevelSpacingF based on the contour levels actually chosen. When the cnLevelSelectionMode is ExplicitLevels, cnLevelSpacingF will be set to the arithmetic average of the spacing between levels.

Default: 5.0

cnMinLevelValF

When the cnLevelSelectionMode is ManualLevels, the value of cnMinLevelValF, if set, determines the lowest contour level. Otherwise, ContourPlot sets the cnMinLevelValF to a value equal to lowest contour level picked.

Default: <dynamic>

cnMaxLevelValF

When the cnLevelSelectionMode is ManualLevels, the value of cnMaxLevelValF, if set, determines the highest contour level. Otherwise, ContourPlot sets the cnMaxLevelValF to a value equal to highest contour level picked.

Default: <dynamic>

cnLevels

An array of floats containing the contour levels used to render the contour plot. If the cnLevelSelectionMode is ExplicitLevels, you may set these values yourself. Otherwise, the ContourPlot object sets the elements of this array.

Default: <dynamic>

cnMonoLevelFlag

When cnMonoLevelFlag is set True, the scalar resource cnLevelFlag sets the level flag controlling the appearance of the line and/or the line label to a single value. In this case, the cnLineLabelInterval resource has no effect. Otherwise, when cnMonoLevelFlag is set False, you can set the level flag for each line individually using the resource cnLevelFlags, or set line labels to appear at uniform contour intervals using the resource cnLineLabelInterval.

Default: False

cnLevelFlag

When cnMonoLevelFlag is set True, this resource of type NhlcnLevelUseMode sets the rendering of all contour levels to one of four possible values:

NoLine: No lines or label appear.
LineOnly: Lines but no labels appear.
LabelOnly: Labels but no lines appear.
LineAndLabel: Both lines and labels appear.

Note that the resources cnLinesOn and cnLineLabelsOn must both be set to True to enable all possible settings of cnLevelFlag.

Default:

cnLevelFlags

When cnMonoLevelFlag is False, cnLevelFlags is an array of type NhlcnLevelUseModeGenArray that allows you individual control over whether a line and/or a line label is to appear at each contour level. It has no effect on contour fill. There are four choices:

NoLine: No line or label appears at the contour level.
LineOnly: Lines but no labels appear at the contour level.
LabelOnly: Labels but no lines appear at the contour level.
LineAndLabel: Both lines and labels appear at the contour level.

Note that cnLinesOn and cnLineLabelsOn exert underlying control over the appearance of contour lines and line labels. If cnLinesOn is set False, no lines will appear regardless of the values of any cnLevelFlags elements; likewise, if cnLineLabels is False, no line labels will appear.

If cnMonoLevelFlag is False and you do not explicitly set cnLevelFlags, the ContourPlot object will set its elements for you based on the value of cnLineLabelInterval. Elements will be set to LineOnly except that if cnLineLabelInterval is greater than 0, elements separated by the interval of cnLineLabelInterval will be set to LineAndLabel. This effect will occur both at initialization and any time you explicitly set cnLineLabelInterval.

Default: <dynamic>

cnLineLabelInterval

When cnMonoLevelFlag is False and you do not explicitly set the array cnLevelFlags, a positive value of cnLineLabelInterval sets the number of levels from a labelled level to the next labelled level. The interval is generated in both directions from the contour level requiring the least number of significant digits to express (with the value 0.0 considered to require zero significant digits). If cnLineLabelInterval is less than or equal to zero then no contour levels are labelled.

Default: 2

cnLinesOn

If this boolean resource is set to False, no contour lines will appear in the contour plot, regardless of the values contained in the cnLevelFlags array resource. It has no effect on line labels.

Default: True

cnLineDrawOrder

This resource of type NhlDrawOrder determines when the contour lines are drawn relative to other elements of the plot. There are three choices:

PreDraw: Draw the contour lines before the standard draw; the lines will be overlaid by any subsequently drawn elements.
Draw: Draw the lines during the standard draw; the lines will overlay any elements drawn during the pre-draw phase, but will underlie elements drawn during the post-draw phase.
PostDraw: Draw the lines after the standard draw; the lines will overlay any elements drawn during the pre-draw and draw phases.

Default: Draw

cnMonoLineColor

When set True, all contour lines are set to a single color, as specified by the value of the scalar resource cnLineColor. Otherwise, the elements of the array resource cnLineColors control the color of each line individually.

Default: True

cnLineColor

When cnMonoLineColor is set True, this resource of type NhlTColorIndex sets a uniform color for all contour lines.

Default: Foreground (1)

cnLineColors

When cnMonoLineColor is False, each element of this array resource of type NhlTColorIndexGenArray inidividually sets the color of the contour line drawn at the corresponding contour level. If the array is not set explicitly it will dynamically default to a set of colors spread numerically over the range of defined HLU color indexes. The colors used will therefore depend on the number of contour levels. If the array currently contains fewer elements than cnLevelCount, more elements will be added to the array and given values according to the default color assignment scheme; existing elements with valid color index values will not be modified.

Default: <dynamic>

cnMonoLineDashPattern

When set True, all contour lines are rendered using the same dash pattern, as specified by the value of the scalar resource cnLineDashPattern. Otherwise, the elements of the array resource cnLineDashPatterns control the dash pattern of each line individually.

Default: True

cnLineDashPattern

When cnMonoLineDashPattern is set True, this resource of type NhlTDashIndex sets a uniform dash pattern for all contour lines.

Default: SolidLine (0)

cnLineDashPatterns

When cnMonoLineDashPattern is False, this array resource of type NhlTDashIndexGenArray inidividually sets the dash pattern of a contour line drawn at the corresponding contour level. If the array is not set explicitly the ContourPlot object will assign sequential dash pattern indexes to each array element (starting with dash pattern index 1, not "SolidLine" (0)) up to the maximum number of existing dash patterns. Thereafter it will repeat the sequence using modular arithmetic. If the array currently contains fewer elements than cnLevelCount, more elements will be added to the array and given values according to the same scheme assignment scheme; existing elements with valid dash pattern index values will not be modified.

Default: <dynamic>

cnMonoLineThickness

When set True, all contour lines are rendered using the same line thickness, as specified by the value of the scalar resource cnLineThicknessF. Otherwise, the elements of the array resource cnLineThicknesses control the dash pattern of each line individually.

Default: True

cnLineThicknessF

When cnMonoLineThickness is True, this resource sets a uniform line thickness for all contour lines.

Default:

cnLineThicknesses

If cnMonoLineThickness is False, each element of this array resource specifies the line thickness of a contour line drawn at the corresponding contour level. If the array is not set explicitly all elements default to the value 1.0. If the array currently contains fewer elements than cnLevelCount, more elements will be added to the array and set to the default value, 1.0; existing elements with valid line thicknesses (greater than 0.0) will not be modified.

Default: 1.0 for all elements

cnLineDashSegLenF

This resource indicates the length of each segment of the dash patterns used to draw contour lines. It is the length in NDC before the dash pattern repeats itself. This resource automatically scales with changes in the size of the viewport of the ContourPlot object. strong>ContourPlot sets the default value of cnLineDashSegLenF dynamically based upon the ratio of the actual plot viewport width to a reference viewport width of 0.5 and a reference dash segment length of 0.075.

Default: 0.075 (for a viewport width of 0.5)

cnFillOn

This boolean resource controls whether the areas between contour levels are filled using a fill pattern (possibly solid) and a fill color.

Default: False

cnRasterModeOn

If this boolean resource is set True, the areas between contour levels are colored using a raster filling technique. The area encompassing the data is divided into an array of square cells. The data value of the center point of each cell determines its color. This is in contrast to the ordinary method of coloring the irregular shapes formed by the boundaries of the lines defining adjacent contour levels. When raster mode is in effect, only solid fill is possible, and therefore the following resources have no effect:

cnFillBackgroundColor
cnMonoFillColor
cnFillColor
cnMonoFillPattern
cnFillPattern
cnFillPatterns
cnMonoFillScale
cnFillScaleF
cnFillScales

The color chosen for each cell is based on the color indexes contained in the cnFillColors array resource unless the cell center is in a missing value area or outside the grid. If the cell center is in a missing value area it is assigned the color index given by the value of the resource cnMissingValFillColor. If it is outside the grid, it is set to the value Background (0).

Processing time, memory requirements, and output quality all vary inversely with the size of the cells in the cell array.

Default: False

cnRasterCellSizeF

This resource defines the length of each side of the squares that make up the cell array when the raster mode of contour filling is enabled by setting cnRasterModeOn True. Its units are NDC. Processing time, memory requirements, and output quality all vary inversely with the value of this resource. Its value scales proportionally to changes in the viewport width, unless you explicitly set cnRasterCellSizeF during the same call. This has the effect of maintaining the rendering at the same level of image quality regardless of its size within the viewport.

Default: <dynamic> -- 0.001 for a viewport width of 0.5

cnFillDrawOrder

This resource of type NhlDrawOrder determines when areas of the contour plot are filled relative to the drawing of other elements of the plot. There are three choices:

PreDraw: Fill contour areas before the standard draw phase; fill areas will be overlaid by any subsequently drawn elements.
Draw: Fill contour areas during the standard draw phase; the fill will overlay any elements drawn during the pre-draw phase, but will underlie elements drawn during the post-draw phase.
PostDraw: Fill contour areas after the standard draw; the area fill overlay any elements drawn during the pre-draw and draw phases.

You must manipulate this resource in order to mask contours within the context of an Overlay of multiple plot objects.

Default: Draw

cnFillBackgroundColor

This resource of type NhlTColorIndex sets the background color used for ContourPlot fill patterns. It only has an effect for fill patterns that are neither SolidFill nor HollowFill. By default, this resource is set to Transparent, resulting in the underlying background appearing in the spaces between the elements of the fill pattern. If set to any other valid color index, the specified color will solidly fill all spaces between the fill pattern elements.

Default: Transparent

cnMonoFillColor

When set True, all contour fill areas are set to a single color, as specified by the value of the scalar resource cnFillColor. When False, the elements of the array resource cnFillColors control the color of each fill area individually.

Default: False

cnFillColor

When cnMonoFillColor is set True, this resource of type NhlTColorIndex sets a uniform fill color for all contour fill areas.

Default: Foreground

cnFillColors

If cnMonoFillColor is False, each element of this array of type NhlTColorIndexGenArray specifies the color of a contour fill area. Note that there is always one more fill area than there are contour levels. The first first element of cnFillColors specifies the fill pattern for any region containing a data value less than the value of cnMinLevelValF while the highest currently used element of cnFillColors specifies the fill pattern for regions containing data values greater than the value of cnMaxLevelValF. Otherwise cnFillColors works in a fashion similiar to cnLineColors. If the array is not set explicitly it will default to a set of color indexes sequentially incremented beginning with color index 1 (NhlFOREGROUND). If the array currently contains fewer elements than cnLevelCount plus, more elements will be added to the array and given values according to the default color assignment scheme; existing elements with valid color index values will not be modified.

Default: <dynamic>

cnMonoFillPattern

When set True, all contour fill areas use a single fill pattern, as specified by the value of the scalar resource cnFillPattern. When False, the elements of the array resource cnFillPatterns control the pattern used for each fill area individually.

Default: True

cnFillPattern

When cnMonoFillPattern is set True, this resource of type NhlTFillIndex sets a uniform pattern for all contour fill areas.

Default:

cnFillPatterns

If cnMonoFillPattern is False, each element of this array of type NhlTFillIndexGenArray specifies the fill pattern used for a contour fill area. Note that there is always one more fill area than there are contour levels. The first first element of cnFillPatterns specifies the fill pattern for any region containing a data value less than the value of cnMinLevelValF while the highest currently used element of cnFillPatterns specifies the fill pattern for regions containing data values greater than the value of cnMaxLevelValF. If the array is not set explicitly the ContourPlot object will assign sequential fill pattern indexes (starting with fill index 1 -- not "SolidFill", which is fill index 0) to each array element up to the maximum number of existing fill patterns. Thereafter it will repeat the sequence using modular arithmetic. If the array currently contains fewer elements than cnLevelCount plus one, more elements will be added to the array and given values according to the same assignment scheme; existing elements with valid fill pattern index values will not be modified.

Default: <dynamic>

cnMonoFillScale

When set True, the all contour fill patterns are scaled by a single factor, as specified by the value of the scalar resource cnFillScale. When False, the elements of the array resource cnFillScales control the scaling applied to the fill pattern assigned to each fill area individually.

Default: True

cnFillScaleF

When cnMonoFillScale is True, this resource sets a uniform scaling value for all contour fill patterns.

Default: 1.0

cnFillScales

When cnMonoFillScale is False, the cnFillScales array resource allows individual control of the scaling of the pattern used for each contour fill area. It has no effect for solid fill (fill pattern "SolidFill", index 0). Values greater than 1.0 make the pattern spacing bigger than the default spacing, resulting in a fill that appears less dense. Values less than 1.0 have the opposite effect. Values less than or equal to 0.0 are invalid, generate a warning message, and are reset to the default value, 1.0.

Note that there is always one more fill area than there are contour levels. If the array is not set explicitly the ContourPlot object will assign the value 1.0 to all elements of the array. If the array currently contains fewer elements than cnLevelCount plus one, more elements will be added to the array and given the same default value of 1.0; existing elements with valid fill scale index values will not be modified.

Default: 1.0 for all elements

cnLabelDrawOrder

This resource of type NhlDrawOrder determines when contour plot labels are drawn relative to the drawing of other elements of the plot. There are three choices:

PreDraw: Draw contour labels before the standard draw phase; the labels areas will be overlaid by any subsequently drawn elements.
Draw: Draw contour labels during the standard draw phase; the labels will overlay any elements drawn during the pre-draw phase as well as fill and contour lines drawn during the standard draw phase, but will underlie elements drawn during the post-draw phase.
PostDraw: Draw contour labels after the standard draw; the labels will overlay any elements drawn during the pre-draw and draw phases as well as lines and fill drawn during the post-draw phase.

Default: Draw

cnLabelMasking

This resource controls whether ContourPlot lines and fill are masked in the areas where ContourPlot labels are to appear. When working with raster type devices, it is seldom necessary to mask for labels, since they can be made to solidly overlay the areas where they appear. Also there is a noticeable performance penalty when labels are masked, so the use of this option is discouraged unless it is necessary.

Default: False

cnLowUseHighLabelRes

If the boolean resource cnLowUseHighLabelRes is set True, all resources applying to low labels, except for cnLowLabelString, take their value from the corresponding high label resources.

Default: False

cnHighUseLineLabelRes

If the boolean resource cnHighUseLineLabelRes is set True, all resources applying to high labels, except for cnHighLabelString and cnHighLabelAngleF, take their value from the corresponding line label resources.

Default: False

cnConstFUseInfoLabelRes

If the boolean resource cnConstFUseInfoLabelRes is set True, all the resources applying to the constant field, except for cnConstFLabelString, take their value from the corresponding informational label resources.

Default: False

cnHighLowLabelOverlapMode

cnHighLowLabelOverlapMode is a resource of type NhlcnHighLowLabelOverlapMode. It controls how high and low labels are allowed to overlap other elements of the ContourPlot plot and has 6 possible settings:

IgnoreOverlap: The ContourPlot object does nothing to prevent high and low labels from overlapping other elements of the ContourPlot plot.
OmitOverHL: The ContourPlot object omits high and low labels that would overlap previously determined high or low labels.
OmitOverVP: The ContourPlot object omits high and low labels that would overlap the edge of the viewport.
OmitOverVPAndHL: The ContourPlot object omits high and low labels that would overlap the edge of the viewport or previously determined high or low labels.
AdjustVP: The ContourPlot object adjusts the position of high and low labels that would overlap the edge of the viewport enough to eliminate the problem.
AdjustVPOmitOverHL: The ContourPlot object adjusts the position of high and low labels that would overlap the edge of the viewport enough to eliminate the problem and omits high and low labels that would overlap previously determined high or low labels.

V4.0 Status Note 6

Default: IgnoreOverlap

cnLabelScalingMode

This resource of type NhlcnLabelScalingMode determines how to scale the numbers representing scalar field data values in the ContourPlot object's labels. cnLabelScalingMode applies to numbers that represent data values in line labels, high and low labels, the informational label, and the constant field label. There are five choices:

ScaleFactor: The ContourPlot object multiplies the data value by the value of cnLabelScaleValueF to obtain the number that appears in the label.
ConfineToRange: The ContourPlot object uses cnLabelScaleValueF as an exclusive upper bound. A scale factor is selected such that the data value with the maximum absolute value will be less than cnLabelScaleValueF, but greater or equal to cnLabelScaleValueF divided by 10.0. As an example, setting cnLabelScaleValueF to 100.0 would result in the number used to represent the maximum absolute data value falling in the range 10.0 to 99.999....
TrimZeros: The ContourPlot object selects a scale factor such that the number representing the data value with the maximum absolute value will have the fewest possible extra zeros. If the maximum absolute value were 245000, for instance, it would scale to 245. If it were 0.000245, it would scale to 0.245. (The zero conventionally placed before the decimal point of a number less than 1.0 is not considered.)
MaxSigDigitsLeft: The ContourPlot object selects a scale factor such that the number representing the data value with the maximum absolute value will have its rightmost significant digit directly to the left of the decimal point. The number of significant digits is determined by the format string resource, cnMaxDataValueFormat.
IntegerLineLabels: The ContourPlot object selects a scale factor such that the numbers representing labelled contour levels (as determined by examination of the values of the cnLabelFlags array) are reduced to integers.

In each case, the scale factor selected is placed into the read-only resource, cnLabelScaleFactorF.

Default: ScaleFactor

cnLabelScaleValueF

The interpretation of cnLabelScaleValueF depends on the value of the enumerated resource cnLabelScalingMode. When cnLabelScalingMode is set to ScaleFactor, data values are multiplied by the value of cnLabelScaleValueF to obtain the numbers appearing in ContourPlot object labels. If cnLabelScalingMode is set to ConfineToRange, the cnLabelScaleValueF represents an exclusive upper bound for the numbers used to represent the data values. For other values of cnLabelScalingMode the cnLabelScaleValueF resource is ignored.

Default: 1.0

cnLabelScaleFactorF

cnLabelScaleFactorF is a read-only resource that contains the current scale factor applied to the scalar field data in order to obtain the numbers used in ContourPlot object labels. The ContourPlot object calculates its value based on the data value with the maximum absolute value, the current mode of the enumerated resource, cnLabelScalingMode, and perhaps the value of cnLabelScaleValueF. Its value may also be influenced by the number of significant digits specified by the format specification resource, cnMaxDataValueFormat.

Default: <dynamic>

cnMaxDataValueFormat

The cnMaxDataValueFormat resource is a string that specifies the printing format for the maximum data value according to the HLU Floating Point Format Specification scheme. This resource serves as a master control for formatting any number representing ScalarField data when used in a ContourPlot label. If the format string for a label type sets sets the dynamic attribute on for any of its numerical format parameters, the parameter's value is determined by the value of the corresponding parameter in the cnMaxDataValueFormat specifier. Thus, you can control the numerical format parameters for all labels by adjusting a single resource. For some format parameters, notably the leftmost significant digit parameter, you must use the dynamic attribute in order to apply the parameter in a meaningful way.

Default: NULL

cnLineLabelsOn

If this boolean resource is set to False, contour line labels will not appear in the contour plot. Note that this resource overrides the values contained in the cnLevelFlags array resource, with respect to line labels but has nothing to do with whether contour lines appear.

Default: True

cnExplicitLineLabelsOn

This boolean resource controls the way ContourPlot handles the cnLineLabelStrings array resource. When set True, ContourPlot will not modify explicitly set values of the line label strings. When cnExplicitLineLabelsOn is set False, ContourPlot ignores values of cnLineLabelStrings set by the user.

Default: False

cnLineLabelPlacementMode

This resource of type NhlcnLineLabelPlacementMode determines the algorithm ContourPlot uses to place line labels. There are three choices:

Constant: Labels are equally-spaced along the lines.
Randomized: ContourPlot places labels using a randomizing algorithm to vary the distance between labels.
V4.0 Status Note 8
Computed: ContourPlot uses a more complex algorithm involving the local gradient, number of contour lines in a region, cumulative change in direction, and an optimum distance value to determine the best location for line labels. This method usually gives the best looking results.
V4.0 Status Note 9

Default: Randomized

cnLineLabelStrings

Each element of the array resource cnLineLabelStrings specifies a string to be drawn at a contour level. Note that there is an element of this array for each contour level, whether or not (based on the contents of the cnLevelFlags array) a label will actually be drawn. If cnExplicitLineLabelsOn is set False, ContourPlot automatically sets the contents of the array to a set of strings representing the values of the contour levels, scaled by the value of cnLabelScaleFactorF, and formatted based on the contents of cnMaxDataValueFormat and cnLineLabelFormat.

If cnExplicitLineLabelsOn is set True, ContourPlot will not modify any initialized element of the array, thus allowing you to set its values to strings of your choice. If you set the resource with an array containing fewer elements than the current number of levels, the remaining elements will be assigned using the automatic method.

Default: <dynamic>

cnMonoLineLabelFontColor

When set True, all contour line labels are rendered using a single color, as specified by the value of the scalar resource cnLineLabelFontColor. When False, the elements of the array resource cnLineLabelFontColors control the color of each line label individually.

Default: True

cnLineLabelFontColor

When cnMonoLineLabelColor is set True, this resource of type NhlTColorIndex sets a uniform color for all contour line labels.

Default: "Foreground"

cnLineLabelFontColors

When cnMonoLineLabelFontColor is False, each element of this array of type NhlTColorIndexGenArray specifies the color of a contour line label. If the array is not set explicitly it will dynamically default to a set of colors spread numerically over the range of defined HLU color indexes. The colors used will therefore depend on the number of contour levels. If the array currently contains fewer elements than cnLevelCount, more elements will be added to the array and given values according to the default color assignment scheme; existing elements with valid color index values will not be modified.

Default: NULL

cnLineLabelFormat

The cnLineLabelFormat resource is a string that specifies the printing format for the numeric portion of line labels according to the HLU Floating Point Format Specification scheme. It does not apply when the user explicitly sets the elements of cnLineLabelStrings. If any of the numerical format parameters have the dynamic attribute on, the corresponding parameter in the cnMaxDataValueFormat resource determines the parameter's value. The default value uses the shorthand notation '*+' to cause all numeric format parameters to be determined dynamically.

Default: "*+g"

cnLineLabelFontHeightF

This resource controls the height in NDC of characters used in the text of line labels. The character width scales proportionally, unless you also modify the aspect ratio using the cnLineLabelFontAspectF resource. The line label text height scales with changes to the viewport width, unless you explicitly set cnLineLabelFontHeightF during the same call.

Default: <dynamic>

cnLineLabelFont

This resource of type NhlFont specifies the font used to render line labels.

Default: 0

cnLineLabelFontAspectF

This resource determines the shape of the line label characters. Values increasing from 1.0 results in thinner characters. Values decreasing from one makes the characters wider. Values less than or equal to 0.0 result in a WARNING message and a restoration of the default value.

Default: 1.3125

cnLineLabelFontThicknessF

Sets the thickness of the line used to draw line label text. The value acts as a multiplier of a (device-dependent) unit thickness. This resource is ignored when the lbLabelFont specifies a filled font (font indexes 21 through 30 and 33 through 37).

Default: 1.0

cnLineLabelFontQuality

This resource of type NhlFontQuality determines the quality of the font used to draw ContourPlot line labels.

Default: High

cnLineLabelConstantSpacingF

Normally when cnLineLabelFontQuality is set to High, the ContourPlot object writes line label text with proportional spacing. Setting the cnLineLabelConstantSpacingF to a value greater than 0.0 overrides this behavior. Instead, the distance from the start of one character to the next is computed by multiplying a single standard character width by the value of cnLineLabelConstantSpacingF. When cnLineLabelConstantSpacingF has a value between 0.0 and 1.0, characters will overlap. A value of 1.0 implies, on average, no space between characters, while values increasing from 1.0 cause the space between characters to grow. This parameter is ignored when cnLineLabelFontQuality is not High. Values less than 0.0 result in an error and are replaced with the default value.

Default: 0.0

cnLineLabelAngleF

When cnLineLabelAngleF has a value less than 0.0, ContourPlot line labels are angled in the direction of the tangent of the contour line at the location of the label. Otherwise, cnLineLabelAngleF specifies the angle in degrees of all contour line labels. If cnLineLabelPlacementMode is set to Constant, this resource has no effect: the line labels are always placed along the contour line.

Default: -1.0

cnLineLabelFuncCode

This resource of type NhlCharacter sets the function code character that the low level utilities will use when parsing the label string.

Default: :

cnLineLabelBackgroundColor

This resource sets the background color used to fill the box surrounding each line label. If you do not want the box to be filled at all, set cnLineLabelBackgroundColor to Transparent (-1). If cnLineLabelPlacementMode is set to Constant, this resource has no effect: a boxed background is not available.

Default: Background

cnLineLabelPerimOn

cnLineLabelPerimOn is a boolean resource that determines whether ContourPlot will draw an outline around the perimeter of the box surrounding contour line labels. If set False no outline will be drawn. If cnLineLabelPlacementMode is set to Constant, this resource has no effect: no perimeter can be drawn around the label.

Default: True

cnLineLabelPerimSpaceF

cnLineLabelPerimSpaceF determines the spacing or margin between the text of the line label and the edge of the line label box as a fraction of the current line label text height. If cnLineLabelPlacementMode is set to Constant, this resource has no effect: no perimeter can be drawn around the label.

Default: 0.33

cnLineLabelPerimColor

This resource sets the hlu color index used to draw the perimeter of the line label box. If cnLineLabelPlacementMode is set to Constant, this resource has no effect: no perimeter can be drawn around the label.

Default: Foreground

cnLineLabelPerimThicknessF

This resource determines the thickness of the perimeter line around the line label box. The value acts as a multiplier of a (device-dependent) unit thickness. If cnLineLabelPlacementMode is set to Constant, this resource has no effect: no perimeter can be drawn around the label.

Default: 1.0

cnHighLabelsOn

If this boolean resource is set to False, ContourPlot will not create labels for highs in the ScalarField data.

Default: True

cnHighLabelString

Specifies the string to use when drawing high labels. The string may contain function codes and/or substitution substrings. ContourPlot will replace the substring "$ZDV$" with a number representing the low at the point where the label is to appear. cnHighLabelFormat determines the format of the number and cnLabelScaleFactorF determines the scale factor applied to the actual data value. Note that the value of cnHighLabelString does not take its value from cnLineLabelString when cnHighUseLowLabelRes is True.

Default: "H:B:$ZDV$:E:"

cnHighLabelFormat

The cnHighLabelFormat resource is a string that specifies the printing format for the numeric portion of high labels according to the HLU Floating Point Format Specification scheme. If any of the numerical format parameters have the dynamic attribute on, the corresponding parameter in the cnMaxDataValueFormat resource determines the parameter's value. The default value uses the shorthand notation '*+' to cause all numeric format parameters to be determined dynamically.

Default: "*+g"

cnHighLabelFontHeightF

This resource controls the height in NDC of characters used in the text of high labels. The character width scales proportionally, unless you also modify the aspect ratio using the cnHighLabelFontAspectF resource. The high label text height scales with changes to the viewport width, unless you explicitly set cnHighLabelFontHeightF during the same call.

Default: <dynamic>

cnHighLabelFont

This resource of type NhlFont specifies the font used to render high labels.

Default: 0

cnHighLabelFontColor

This resource specifies the hlu color index used to render high label text. If cnHighUseLineLabelRes is True, this resource takes its value from the first element of the cnLineLabelFontColors array.

Default: True

cnHighLabelFontAspectF

This resource determines the shape of the high label characters. Values increasing from 1.0 results in thinner characters. Values decreasing from one makes the characters wider. Values less than or equal to 0.0 result in a WARNING message and a restoration of the default value.

Default: 1.3125

cnHighLabelFontThicknessF

Sets the thickness of the line used to draw high label text. The value acts as a multiplier of a (device-dependent) unit thickness. This resource is ignored when the lbLabelFont specifies a filled font (font indexes 21 through 30 and 33 through 37).

Default: 1.0

cnHighLabelFontQuality

This resource of type NhlFontQuality determines the quality of the font used to draw ContourPlot high labels.

Default: High

cnHighLabelConstantSpacingF

Default: 0.0

cnHighLabelAngleF

This resource specifies the angle in degrees of high label text and its surrounding box. Note that the value of cnHighLabelAngleF does not take its value from cnLineLabelAngleF when cnHighUseLowLabelRes is True.

Default: 0.0

cnHighLabelFuncCode

This resource of type NhlCharacter sets the function code character that the low level utilities will use when parsing the high label string.

Default: :

cnHighLabelBackgroundColor

This resource sets the background color used to fill the box surrounding each high label. If you do not want the box to be filled at all, set cnHighLabelBackgroundColor to Transparent (-1).

Default: Background

cnHighLabelPerimOn

cnHighLabelPerimOn is a boolean resource that determines whether ContourPlot will draw an outline around the perimeter of the box surrounding contour high labels. If set False no outline will be drawn.

Default: True

cnHighLabelPerimSpaceF

cnHighLabelPerimSpaceF determines the spacing or margin between the text of the high label and the edge of the high label box as a fraction of the current high label text height.

Default: 0.33

cnHighLabelPerimColor

This resource sets the hlu color index used to draw the perimeter of the high label box.

Default: Foreground

cnHighLabelPerimThicknessF

This resource determines the thickness of the perimeter line around the high label box. The value acts as a multiplier of a (device-dependent) unit thickness.

Default: 1.0

cnLowLabelsOn

If this boolean resource is set to False, ContourPlot will not create labels for lows in the ScalarField data.

Default: True

cnLowLabelString

Specifies the string to use when drawing low labels. The string may contain function codes and/or substitution substrings. ContourPlot will replace the substring "$ZDV$" with a number representing the low at the point where the label is to appear. cnLowLabelFormat determines the format of the number and cnLabelScaleFactorF determines the scale factor applied to the actual data value. Note that the value of cnLowLabelString does not take its value from cnHighLabelString when cnLowUseHighLabelRes is True.

Default: "L:B:$ZDV$:E:"

cnLowLabelFormat

The cnLowLabelFormat resource is a string that specifies the printing format for the numeric portion of low labels according to the HLU Floating Point Format Specification scheme. If any of the numerical format parameters have the dynamic attribute on, the corresponding parameter in the cnMaxDataValueFormat resource determines the parameter's value. The default value uses the shorthand notation '*+' to cause all numeric format parameters to be determined dynamically.

Default: "*+g"

cnLowLabelFontHeightF

This resource controls the height in NDC of characters used in the text of low labels. The character width scales proportionally, unless you also modify the aspect ratio using the cnLowLabelFontAspectF resource. The low label text height scales with changes to the viewport width, unless you explicitly set cnLowLabelFontHeightF during the same call.

Default: <dynamic>

cnLowLabelFont

This resource of type NhlFont specifies the font used to render low labels.

Default: 0

cnLowLabelFontColor

This resource specifies the hlu color index used to render low label text.

Default: True

cnLowLabelFontAspectF

This resource determines the shape of the low label characters. Values increasing from 1.0 results in thinner characters. Values decreasing from one makes the characters wider. Values less than or equal to 0.0 result in a WARNING message and a restoration of the default value.

Default: 1.3125

cnLowLabelFontThicknessF

Sets the thickness of the line used to draw low label text. The value acts as a multiplier of a (device-dependent) unit thickness. This resource is ignored when the lbLabelFont specifies a filled font (font indexes 21 through 30 and 33 through 37).

Default: 1.0

cnLowLabelFontQuality

This resource of type NhlFontQuality determines the quality of the font used to draw ContourPlot low labels.

Default: High

cnLowLabelConstantSpacingF

Default: 0.0

cnLowLabelAngleF

This resource specifies the angle in degrees of low label text and its surrounding box.

Default: 0.0

cnLowLabelFuncCode

This resource of type NhlCharacter sets the function code character that the low level utilities will use when parsing the low label string.

Default: :

cnLowLabelBackgroundColor

This resource sets the background color used to fill the box surrounding each low label. If you do not want the box to be filled at all, set cnLowLabelBackgroundColor to Transparent (-1).

Default: Background

cnLowLabelPerimOn

cnLowLabelPerimOn is a boolean resource that determines whether ContourPlot will draw an outline around the perimeter of the box surrounding contour low labels. If set False no outline will be drawn.

Default: True

cnLowLabelPerimSpaceF

cnLowLabelPerimSpaceF determines the spacing or margin between the text of the low label and the edge of the low label box as a fraction of the current low label text height.

Default: 0.33

cnLowLabelPerimColor

This resource sets the hlu color index used to draw the perimeter of the low label box.

Default: Foreground

cnLowLabelPerimThicknessF

This resource determines the thickness of the perimeter line around the low label box. The value acts as a multiplier of a (device-dependent) unit thickness.

Default: 1.0

cnInfoLabelOn

If this boolean resource is set to False, ContourPlot will not draw an informational label.

Default: True

cnInfoLabelString

Specifies the string to use when drawing an informational label. The string may contain function codes and/or substitution substrings. ContourPlot will replace the following substrings with numeric values:

$CIU$: The contour interval used (value of cnLevelSpacing)
$CMN$: The minimum contour level (first element of cnLevels)
$CMX$: The maximum contour level
$SFU$: The scale factor used (value of cnLabelScaleFactorF
$ZMN$: The minimum data value
$ZMX$: The maximum data value

cnInfoLabelFormat determines the format of the each number and except for the number generated from $SFU$, all values are scaled by the value of cnLabelScaleFactorF.

Default: "CONTOUR FROM $CMN$ TO $CMX$ BY $CIU$"

cnInfoLabelFormat

The cnInfoLabelFormat resource is a string that specifies the printing format for the numbers generated from substitution substrings in the cnInfoLabelString. according to the HLU Floating Point Format Specification scheme. If any of the numerical format parameters have the dynamic attribute on, the corresponding parameter in the cnMaxDataValueFormat resource determines the parameter's value. The default value uses the shorthand notation '*+' to cause all numeric format parameters to be determined dynamically.

Default: "*+g"

cnInfoLabelTextDirection

This resource of type NhlTextDirection specifies the direction of the text in the informational label. There are three choices of which two are actually the same:

Down: Each character is placed below the previous character in the text string.
Across: Each character is placed to the right of the previous character in the text string.

These descriptions apply before any rotation due to cnInfoLabelAngleF is applied to the informational label.

Default: Across

cnInfoLabelFontHeightF

This resource controls the height in NDC of characters used in the text of the informational label. The character width scales proportionally, unless you also modify the aspect ratio using the cnInfoLabelFontAspectF resource. The info label text height scales with changes to the viewport width, unless you explicitly set cnInfoLabelFontHeightF during the same call.

Default: <dynamic>

cnInfoLabelFont

This resource of type NhlFont specifies the font used to render the informational label.

Default: 0

cnInfoLabelFontColor

This resource specifies the hlu color index used to render informational label text.

Default: True

cnInfoLabelFontAspectF

This resource determines the shape of the informational label characters. Values increasing from 1.0 results in thinner characters. Values decreasing from one makes the characters wider. Values less than or equal to 0.0 result in a WARNING message and a restoration of the default value.

Default: 1.3125

cnInfoLabelFontThicknessF

Sets the thickness of the line used to draw informational label text. The value acts as a multiplier of a (device-dependent) unit thickness. This resource is ignored when the lbLabelFont specifies a filled font (font indexes 21 through 30 and 33 through 37).

Default: 1.0

cnInfoLabelFontQuality

This resource of type NhlFontQuality determines the quality of the font used to draw the ContourPlot informational label.

Default: High

cnInfoLabelConstantSpacingF

Normally when cnLineLabelFontQuality is set to High, the ContourPlot object writes informational label text with proportional spacing. Setting the cnInfoLabelConstantSpacingF to a value greater than 0.0 overrides this behavior. Instead, the distance from the start of one character to the next is computed by multiplying a single standard character width by the value of cnLineLabelConstantSpacingF. When cnLineLabelConstantSpacingF has a value between 0.0 and 1.0, characters will overlap. A value of 1.0 implies, on average, no space between characters, while values increasing from 1.0 cause the space between characters to grow. This parameter is ignored when cnInfoLabelFontQuality is not High. Values less than 0.0 result in an error and are replaced with the default value.

Default: 0.0

cnInfoLabelAngleF

This resource specifies the angle in degrees of the informational label text and its surrounding box.

Default: 0.0

cnInfoLabelFuncCode

This resource of type NhlCharacter sets the function code character that the low level utilities will use when parsing the informational label string.

Default: :

cnInfoLabelBackgroundColor

This resource sets the background color used to fill the box surrounding the informational label. If you do not want the box to be filled at all, set cnInfoLabelBackgroundColor to Transparent (-1).

Default: Background

cnInfoLabelPerimOn

cnInfoLabelPerimOn is a boolean resource that determines whether ContourPlot will draw an outline around the perimeter of the box surrounding contour informational label. If set False no outline will be drawn.

Default: True

cnInfoLabelPerimSpaceF

cnInfoLabelPerimSpaceF determines the spacing or margin between the text of the informational label and the edge of the informational label box as a fraction of the current label text height.

Default: 0.33

cnInfoLabelPerimColor

This resource sets the hlu color index used to draw the perimeter of the informational label box.

Default: Foreground

cnInfoLabelPerimThicknessF

This resource determines the thickness of the perimeter line around the informational label box. The value acts as a multiplier of a (device-dependent) unit thickness.

cnInfoLabelZone

ContourPlot implements the informational label as an embedded annotation. cnInfoLabelZone specifies the PlotManager zone assigned to the informational annotation. The PlotManager Location Control Model requires this resource to allow control of the informational label consistent with other annotations. If cnInfoLabelZone is set to 0, the positional origin is the center of the plot viewport; otherwise it is on or outside one of the sides of the viewport.

If you create a ContourPlot object without an active PlotManager, by setting tfPlotManagerOn False, then ContourPlot manages the informational annotation by itself. In this case the cnInfoLabelZone resource is not as meaningful.

Default: 5

cnInfoLabelSide

This resource of type NhlPosition determines where to place the informational annotation in relation to the sides of the plot object. The PlotManager Location Control Model requires this resource to allow control of the informational label consistent with other annotations. Its value determines a coordinate system origin and the direction of the positional resources, cnInfoLabelParallelPosF and cnInfoLabelOrthogonalPosF. It also constrains the value of cnInfoLabelJust appropriately. There are four settings, which behave as follows, unless cnInfoLabelZone is set to one of the special zones (0 or 1):

Top: The PlotManager locates the informational label annotation relative to a line parallelling the top viewport boundary. cnInfoLabelOrthogonalPosF increases in the direction of increasing NDC Y-Axis values and is constrained to positive values. cnInfoLabelParallelPosF increases in the direction of increasing NDC X-Axis values. cnInfoLabelJust is constrained to BottomRight, BottomCenter, or BottomLeft.
Bottom: The PlotManager locates the informational label annotation relative to a line parallelling the bottom viewport boundary. cnInfoLabelOrthogonalPosF increases in the direction of decreasing NDC Y-Axis values and is constrained to positive values. cnInfoLabelParallelPosF increases in the direction of increasing NDC X-Axis values. cnInfoLabelJust is constrained to TopRight, TopCenter, or TopLeft.
Right: The PlotManager locates the informational label annotation relative to a line parallelling the right viewport boundary. cnInfoLabelOrthogonalPosF increases in the direction of increasing NDC X-Axis values and is constrained to positive values. cnInfoLabelParallelPosF increases in the direction of increasing NDC Y-Axis values. cnInfoLabelJust is constrained to TopLeft, CenterLeft, or BottomLeft.
Left: The PlotManager locates the informational label annotation relative to a line parallelling the left viewport boundary. cnInfoLabelOrthogonalPosF increases in the direction of decreasing NDC X-Axis values and is constrained to positive values. cnInfoLabelParallelPosF increases in the direction of increasing NDC Y-Axis values. cnInfoLabelJust is constrained to TopRight, CenterRight, or BottomRight.

If cnInfoLabelZone is set to 0, The PlotManager locates the informational label annotation relative to the viewport center. If cnInfoLabelZone is 1, the direction of the cnInfoLabelOrthogonalPosF is opposite to the specification given above. Also if the cnInfoLabelZone is either 0 or 1, cnInfoLabelJust is not constrained, and cnInfoLabelOrthogonalPosF may take on negative values.

Default: Bottom

cnInfoLabelParallelPosF

cnInfoLabelParallelPosF specifies the coordinate of the base location of the informational label annotation parallel to the current cnInfoLabelSide and directed towards increasing NDC values. The PlotManager Location Control Model requires this resource to allow control of the informational label consistent with other annotations.

Default: 1.0

cnInfoLabelOrthogonalPosF

cnInfoLabelOrthogonalPosF sets the coordinate of the base location of the informational label annotation orthogonal to the current cnInfoLabelSide and directed away from the center of the viewport. The PlotManager Location Control Model requires this resource to allow control of the informational label consistent with other annotations.

Default: 0.02

cnInfoLabelJust

This resource of type NhlJustification, after constraint to an appropriate value based on cnInfoLabelSide, sets the justification of the informational label annotation with respect to its base location. The PlotManager Location Control Model requires this resource to allow control of the informational label consistent with other annotations.

Default: TopRight

cnNoDataLabelOn

This boolean resource, when set True, causes a label to appear when ContourPlot is drawn without any data having been provided. Except for the label string, all attributes of this label, including its position, are set using resources belonging to the constant field label. When set False, no such label appears.

Default: True

cnNoDataLabelString

This resource contains the string that appears in the 'No Data' label if you draw a ContourPlot object without providing any data. No substitution substrings are allowed in this label, since all the substitutions depend on data being available. Except for the boolean switch that turns it on and off, all attributes of this label, including its position, are set using resources belonging to the constant field label.

Default: "NO CONTOUR DATA"

cnConstFLabelOn

The ContourPlot object draws a constant field label annotation only when cnConstFLabelOn is set True and the ScalarField data is determined to have a single constant value within the limits of the available precision or when no ScalarField data supplied.

Default: True

cnConstFLabelString

Specifies the string to use when drawing an constant field label. The string may contain function codes and/or substitution substrings. ContourPlot will replace the substring $ZDV$ with a number representing the constant field value. cnConstFLabelFormat determines the format of the number; its value will be scaled by the value of cnLabelScaleFactorF.

Default: "CONSTANT FIELD - VALUE IS $ZDV$"

cnConstFLabelFormat

The cnConstFLabelFormat resource is a string that specifies the printing format for the number generated from a substitution substring in the cnConstFLabelString according to the HLU Floating Point Format Specification scheme. If any of the numerical format parameters have the dynamic attribute on, the corresponding parameter in the cnMaxDataValueFormat resource determines the parameter's value. The default value uses the shorthand notation '*+' to cause all numeric format parameters to be determined dynamically.

Default: "*+g"

cnConstFLabelTextDirection

This resource of type NhlTextDirection specifies the direction of the text in the constant field label. There are three choices of which two are actually the same:

Down: Each character is placed below the previous character in the text string.
Across: Each character is placed to the right of the previous character in the text string.

These descriptions apply before rotation due to cnInfoLabelAngleF.

Default: Across

cnConstFLabelFontHeightF

This resource controls the height in NDC of characters used in the text of the constant field label. The character width scales proportionally, unless you also modify the aspect ratio using the cnConstFLabelFontAspectF resource. The info label text height scales with changes to the viewport width, unless you explicitly set cnConstFLabelFontHeightF during the same call.

Default: <dynamic>

cnConstFLabelFont

This resource of type NhlFont specifies the font used to render the constant field label.

Default: 0

cnConstFLabelFontColor

This resource specifies the hlu color index used to render constant field label text.

Default: True

cnConstFLabelFontAspectF

This resource determines the shape of the constant field label characters. Values increasing from 1.0 results in thinner characters. Values decreasing from one makes the characters wider. Values less than or equal to 0.0 result in a WARNING message and a restoration of the default value.

Default: 1.3125

cnConstFLabelFontThicknessF

Sets the thickness of the line used to draw constant field label text. The value acts as a multiplier of a (device-dependent) unit thickness. This resource is ignored when the lbLabelFont specifies a filled font (font indexes 21 through 30 and 33 through 37).

Default: 1.0

cnConstFLabelFontQuality

This resource of type NhlFontQuality determines the quality of the font used to draw the ContourPlot constant field label.

Default: High

cnConstFLabelConstantSpacingF

Normally when cnLineLabelFontQuality is set to High, the ContourPlot object writes constant field label text with proportional spacing. Setting the cnConstFLabelConstantSpacingF to a value greater than 0.0 overrides this behavior. Instead, the distance from the start of one character to the next is computed by multiplying a single standard character width by the value of cnLineLabelConstantSpacingF. When cnLineLabelConstantSpacingF has a value between 0.0 and 1.0, characters will overlap. A value of 1.0 implies, on average, no space between characters, while values increasing from 1.0 cause the space between characters to grow. This parameter is ignored when cnConstFLabelFontQuality is not High. Values less than 0.0 result in an error and are replaced with the default value.

Default: 0.0

cnConstFLabelAngleF

This resource specifies the angle in degrees of the constant field label text and its surrounding box.

Default: 0.0

cnConstFLabelFuncCode

This resource of type NhlCharacter sets the function code character that the low level utilities will use when parsing the constant field label string.

Default: :

cnConstFLabelBackgroundColor

This resource sets the background color used to fill the box surrounding the constant field label. If you do not want the box to be filled at all, set cnConstFLabelBackgroundColor to Transparent (-1).

Default: Background

cnConstFLabelPerimOn

cnConstFLabelPerimOn is a boolean resource that determines whether ContourPlot will draw an outline around the perimeter of the box surrounding contour constant field label. If set False no outline will be drawn.

Default: True

cnConstFLabelPerimSpaceF

cnConstFLabelPerimSpaceF determines the spacing or margin between the text of the constant field label and the edge of the constant field label box as a fraction of the current label text height.

Default: 0.33

cnConstFLabelPerimColor

This resource sets the hlu color index used to draw the perimeter of the constant field label box.

Default: Foreground

cnConstFLabelPerimThicknessF

This resource determines the thickness of the perimeter line around the constant field label box. The value acts as a multiplier of a (device-dependent) unit thickness.

cnConstFLabelZone

ContourPlot implements the constant field label as an embedded annotation. cnConstFLabelZone specifies the PlotManager zone assigned to the constant field annotation. The PlotManager Location Control Model requires this resource to allow control of the constant field label consistent with other annotations. If cnConstFLabelZone is set to 0, the positional origin is the center of the plot viewport; otherwise it is on or outside one of the sides of the viewport.

If you create a ContourPlot object without an active PlotManager, by setting tfPlotManagerOn False, then ContourPlot manages the constant field annotation by itself. In this case the cnConstFLabelZone resource is not as meaningful.

Default: 0

cnConstFLabelSide

This resource of type NhlPosition determines where to place the constant field annotation in relation to the sides of the plot object. The PlotManager Location Control Model requires this resource to allow control of the constant field label consistent with other annotations. Its value determines a coordinate system origin and the direction of the positional resources, cnConstFLabelParallelPosF and cnConstFLabelOrthogonalPosF. It also constrains the value of the cnConstFLabelJust appropriately. There are four settings, which behave as follows, unless cnConstFLabelZone is set to one of the special zones (0 or 1):

Top: The PlotManager locates the constant field label annotation relative to a line parallelling the top viewport boundary. cnConstFLabelOrthogonalPosF increases in the direction of increasing NDC Y-Axis values and is constrained to positive values. cnConstFLabelParallelPosF increases in the direction of increasing NDC X-Axis values. cnConstFLabelJust is constrained to BottomRight, BottomCenter, or BottomLeft.
Bottom: The PlotManager locates the constant field label annotation relative to a line parallelling the bottom viewport boundary. cnConstFLabelOrthogonalPosF increases in the direction of decreasing NDC Y-Axis values and is constrained to positive values. cnConstFLabelParallelPosF increases in the direction of increasing NDC X-Axis values. cnConstFLabelJust is constrained to TopRight, TopCenter, or TopLeft.
Right: The PlotManager locates the constant field label annotation relative to a line parallelling the right viewport boundary. cnConstFLabelOrthogonalPosF increases in the direction of increasing NDC X-Axis values and is constrained to positive values. cnConstFLabelParallelPosF increases in the direction of increasing NDC Y-Axis values. cnConstFLabelJust is constrained to TopLeft, CenterLeft, or BottomLeft.
Left: The PlotManager locates the constant field label annotation relative to a line parallelling the left viewport boundary. cnConstFLabelOrthogonalPosF increases in the direction of decreasing NDC X-Axis values and is constrained to positive values. cnConstFLabelParallelPosF increases in the direction of increasing NDC Y-Axis values. cnConstFLabelJust is constrained to TopRight, CenterRight, or BottomRight.

If cnConstFLabelZone is set to 0, The PlotManager locates the constant field label annotation relative to the viewport center. If cnConstFLabelZone is 1, the direction of the cnConstFLabelOrthogonalPosF is opposite to the specification given above. Also if the cnConstFLabelZone is either 0 or 1, cnConstFLabelJust is not constrained, and cnConstFLabelOrthogonalPosF may take on negative values.

Default: Bottom

cnConstFLabelParallelPosF

cnConstFLabelParallelPosF specifies the coordinate of the base location of the constant field label annotation parallel to the current cnConstFLabelSide and directed towards increasing NDC values. The PlotManager Location Control Model requires this resource to allow control of the constant field label consistent with other annotations.

Default: 0.0

cnConstFLabelOrthogonalPosF

cnConstFLabelOrthogonalPosF sets the coordinate of the base location of the constant field label annotation orthogonal to the current cnConstFLabelSide and directed away from the center of the viewport. The PlotManager Location Control Model requires this resource to allow control of the constant field label consistent with other annotations.

Default: 0.0

cnConstFLabelJust

This resource of type NhlJustification, after constraint to an appropriate value based on cnConstFLabelSide, sets the justification of the constant field label annotation with respect to its base location. The PlotManager Location Control Model requires this resource to allow control of the constant field label consistent with other annotations.

Default: CenterCenter

cnMissingValPerimOn

If set True, this boolean resource specifies that perimeter lines be drawn around missing value areas in the ContourPlot plot.

Default: False

cnMissingValPerimThicknessF

This resource determines the thickness of perimeter lines around missing value areas. The value acts as a multiplier of a (device-dependent) unit thickness.

Default: 1.0

cnMissingValPerimDashPattern

This resource sets the HLU index of a dash pattern used to render perimeter lines around missing value areas.

Default: 0

cnMissingValPerimColor

This resource sets the HLU index of the color used to render perimeter lines around missing value areas.

Default: Foreground

cnMissingValFillColor

This resource sets the HLU index of the color used to fill missing value areas. If cnMissingValFillColor has the value Transparent (-1), there will be no fill of the missing value area, regardless of the setting of cnMissingValFillPattern.

Default: Background

cnMissingValFillPattern

This resource sets the HLU index of the fill pattern used to fill missing value areas. If cnMissingValFillPattern has the value HollowFill (-1), there will be no fill of the missing value area, regardless of the setting of cnMissingValFillColor.

Default: HollowFill

cnMissingValFillScaleF

The cnMissingValFillScaleF resource controls the scaling of the pattern used for missing values fill areas. It has no effect for solid fill (fill pattern index Solid or 0). Values greater than 1.0 make the pattern spacing bigger than the default spacing, resulting in a fill that appears less dense. Values less than 1.0 have the opposite effect. Values less than or equal to 0.0 are invalid, generate a warning message, and are reset to the default value, 1.0.

Default: 1.0

cnGridBoundPerimOn

If set True, this boolean resource specifies that a perimeter line be drawn around the grid boundary (extent of the ScalarField data) in the ContourPlot plot.

Default: False

cnGridBoundPerimThicknessF

This resource determines the thickness of the perimeter line around the grid boundary. The value acts as a multiplier of a (device-dependent) unit thickness.

Default: 1.0

cnGridBoundPerimDashPattern

This resource sets the HLU index of a dash pattern used to render the perimeter line around the grid boundary.

Default: 0

cnGridBoundPerimColor

This resource sets the HLU index of the color used to render the perimeter line around the grid boundary.

Default: Foreground

cnOutOfRangePerimOn

If set True, this boolean resource specifies that perimeter lines be drawn around areas where the ScalarField data falls outside the current data boundaries of the plot.

Default: False

cnOutOfRangePerimThicknessF

This resource determines the thickness of perimeter lines around the edge of out of range areas. The value acts as a multiplier of a (device-dependent) unit thickness.

Default: 1.0

cnOutOfRangePerimDashPattern

This resource sets the HLU index of a dash pattern used to render perimeter lines around the edge of out of range areas.

Default: 0

cnOutOfRangePerimColor

This resource sets the HLU index of the color used to render perimeter lines around the edge of out of range areas.

Default: Foreground

cnSmoothingOn

When the boolean resource cnSmoothingOn is True, the ContourPlot object will smooth the contours using cubic splines under tension. The resources cnSmoothingTensionF and cnSmoothingDistanceF control the parameters of the smoothing algorithm. Note that when smoothing is turned on, it is possible in some cases for adjacent contour lines to cross each other. In this case, you will need to adjust the cnSmoothingTensionF experimentally in order to eliminate the problem.

Default: False

cnSmoothingTensionF

If you give cnSmoothingTensionF a value of 0.0, smoothing is turned off. If you give it a negative value, the ContourPlot object performs smoothing prior to any transformations of the data space; if you make it positive smoothing takes place after any data space transformations. Small absolute values on the order of 0.001 give 'loopy' curves, which are rather likely to cross each other. Large absolute values give tight nearly polygonal curves. Note that if cnMaxPointDistanceF is set to a non-zero value smoothing will not work properly unless is is applied prior to the transformation of the data space. Therefore you should always set cnSmoothingTensionF to a negative value when cnMaxPointDistanceF is non-zero.

V4.0 Status Note 13

Default: -2.5

cnSmoothingDistanceF

cnSmoothingDistanceF sets the distance between points used to draw the smoothed contour lines. It is expressed as a fraction of the width of the window in the coordinate system in which smoothing is being performed. Note that processing time is affected greatly by the value given to the smoothing distance. Smaller values add to the processing time.

Default: 0.01

cnMaxPointDistanceF

Controls the maximum distance both along the width and height of the viewport allowed before checking for a discontinous jump in the mapped coordinate points. The value specifies a fraction of the view width for the width check and a fraction of the view height for the height check. A value of 0.0 for this resource turns off this form of checking altogether. When non-zero, this value should not be set less than 0.001 or greater than 0.1. Smaller values increase processing time. Note that if cnMaxPointDistanceF is set to a non-zero value contour smoothing will not work properly unless is is applied prior to the transformation of the data space. Therefore you should always set cnSmoothingTensionF to a negative value when cnMaxPointDistanceF is non-zero.

Default: 0.05

cnExplicitLabelBarLabelsOn

This boolean resource allows you control the labels that appear in the ContourPlot LabelBar explicitly. When set True, ContourPlot does not block the LabelBar resources lbLabelStrings and lbLabelAlignment. Therefore you can directly control both the contents of the LabelBar's label strings and their alignment with respect to the label boxes. When cnExplicitLabelBarLabelsOn is set False, ContourPlot sets both of these resources based on the current contour line labels and the value of the resource cnLabelBarEndLabelsOn. If you set this resource True but do not set the lbLabelStrings array resource, ContourPlot will set it for you one time. This allows you to get an initial set of strings as a starting point for any customized tweaking you wish to perform.

Default: False

cnLabelBarEndLabelsOn

When this boolean resource is set True and cnExplicitLabelBarLabelsOn is False, ContourPlot creates labels for the two ends of the LabelBar. The label at one end will be a string representation of the minimum value in the data set, and at the other end will be a string representation of the maximum value in the data set. Both strings will be formatted according to the format specification in effect for the other labels provided by ContourPlot to the LabelBar.

Default: False

cnExplicitLegendLabelsOn

This boolean resource allows you control the labels that appear in the ContourPlot Legend explicitly. When set True, ContourPlot does not block the Legend resource lgLabelStrings. Therefore you can directly control the content of the Legend's label strings. When cnExplicitLegendLabelsOn is set False, ContourPlot sets lgLabelStrings based on the value of the current contour line labels. If you set this resource True but do not set the lbLabelStrings array resource, ContourPlot will set it for you one time. This allows you to get an initial set of strings as a starting point for any customized tweaking you wish to perform.

Default: False

cnLegendLevelFlags

This array resource of type NhlcnLevelUseModeGenArray allows you to control which of the lines representing contour levels are to appear in the ContourPlot Legend. You can also control whether the lines that do appear are to get a line label. Although the type allows for four choices, this resource supports only three of them:

NoLine: Do not draw a line representing this contour level in the Legend.
LineOnly: Draw a line representing this contour level but no label in the Legend.
LabelOnly: Currently, if an element is set to this value, it is treated the same as if it were set to NoLine.
LineAndLabel: Draw a line representing this contour level along with a line label in the Legend.

If you set this resource with an array containing fewer elements than the current number of contour levels, additional elements are supplied and set to the value NoLine.

Default: NULL

Reference Manual Control Panel

NG4 Home, Index, Examples, Glossary, Feedback, Ref Contents, Ref WhereAmI?

$Revision: 1.12 $ $Date: 1995/07/26 23:29:25 $