NCAR Graphics

What is NCAR Graphics?

NCAR Graphics offers a wide range of capabilities for the display of numerical data. Its versatility has helped researchers throughout the world make sense of massive quantities of data - whether the task be visualizing solar convection fields, particle accelerator magnetics, the Antarctic ozone hole, water movement in the ocean, or some other observed or calculated data.

NCAR Graphics conforms to the FORTRAN 77, C, and Graphical Kernel System (GKS) standards. These are all ANSI (American National Standards Institute) standards. NCAR Graphics produces a graphics metafile in conformance with the binary encoding of the ANSI CGM standard. A level 0A GKS package (with certain level 2A enhancements) is distributed with NCAR Graphics, as well as a CGM viewer that plots to many different devices. You may implement the supplied GKS and CGM viewing packages, or use any other package of your choice. Using a higher-level GKS package will allow you to integrate the functionality of that package into NCAR Graphics.

Graphs and Grids

Autograph draws and annotates curves or families of curves.

Histogram is a general-purpose utility for drawing bar charts. Gridall draws graph paper, backgrounds, perimeters, and so forth.

Contours

Conpack* draws black-and-white or color contour plots from regularly spaced (gridded) data. For irregularly spaced (random) data, we suggest that you use the provided Bivar routines to interpolate from random data to gridded data, and then use Conpack to produce the needed contours. New Conpack features include inverse map transformations, raster contouring using cell-array output, and hachuring capabilities.

Dashed Lines

Dashline draws dashed lines and provides a range of labeling and smoothing capabilities.

Maps

Ezmap* plots continental, U.S. state, and world political outlines using one of ten projections. A great-circle interpolator is a new feature in 3.2. Ezmap output may be redirected to routines in the Areas utility, letting you create solid-colored world maps. Ezmap also lets you draw lines on a map that are masked by the areas created by the area map (lines of latitude and longitude omitted over land masses, for example).

Area Fill

Softfill fills polygons using solid fill, parallel solid lines, rows of dots, rows of polymarkers, or rows of characters. You can use it to do crosshatching and specify dot and line patterns, and you may use color. Areas creates an area map from a set of edges that divide a two-dimensional plane into areas. The area map may then be used in a number of ways, such as in conjunction with Ezmap to create solid-colored maps.

Field Flows

Vectors* creates a two-dimensional vector field display by drawing arrows at each grid point of a rectangular lattice, with arrow length representing magnitude. Version 3.2 adds the ability to color the vectors according to data contained in a scalar field, such as temperature or pressure. Streamlines* represents a vector field by plotting flow lines with arrowheads indicating the direction of the flow. Both utilities now fully support coordinate-system mappings, including polar transformations and all the Ezmap projections. In addition, both utilities have added a masking capability to enhance support for overlays.

Text, Labels, and Legends

Plotchar* uses high-quality filled fonts (new) and optional outlining and shading (new) to plot publication-quality characters. You may choose superscripting and subscripting, character quality, text size, angle, and position on the plotter frame. You may also subject the characters to an arbitrary transformation, such as onto the surface of a globe - Plotchar will automatically take care of clipping characters at boundaries where the characters should disappear. A complete set of the WMO weather symbols is also available (new). Labelbar draws a rectangular bar that may be filled, using color or patterns, and labeled to serve as a key for a filled plot.

Three-dimensional Displays

Isosurface* creates iso-surfaces (with hidden lines removed) from a three- dimensional array. New capability in this utility includes the ability to interpolate a surface to a higher resolution. Surface provides a three- dimensional display of a function of two variables (with hidden lines removed), while Threed provides three-dimensional line-drawing capabilities.

Color Conversion

Colconv converts color specifications from any one of the following color spaces to any other: Some conversions can be done with a single call; others require two calls.

Movies

Gflash supports a limited picture segmentation capability. Parts of pictures can be saved in buffers and inserted into any subsequent picture. Scrolled_title produces scrolled or stationary movie titles. Color is available, as well as fade in and fade out.

How to Use

To print a meta file: 
/usr/local/bin/ctrans -d ps.mono yourfilename| lpr -Pprintername
To view a meta file in X: 
/usr/local/bin/ctrans -d X11 yourfilename

Availability

NCAR Graphics is available on the Suns and SGIs.

Frequently Asked Questions

Press here for the FAQ.

On-line Documentation

NCAR Graphics Version 3.2.1 Documentation

NCAR Graphics Version 4.0 Documentation (remote) NCAR Graphics Version 4.0 Documentation (local)

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