ContourPlot example 14

Drawing contours of wind speeds overlayed on a map plot.

This example demonstrates how to read two netCDF variables, U and V winds, and produce a contour plot of the wind speed over a map plot. The names of the example codes that create this plot are cn14c.c, cn14f.f, and cn14n.ncl.


There is no resource file for this example, as all the resources are set in the source code.

A detailed discussion about how to create the plot appears in the comments of the source code for the example.

Creating the plot using HLU C library calls

The HLU C program that generates this plot is called cn14c.c.

Creating the plot using HLU FORTRAN library calls

The HLU FORTRAN program that generates this plot is called cn14f.f.

Creating the plot using NCL

The NCL script that generates this plot is called cn14n.ncl.

The data

The data for this plot is from a netCDF file (created by NCL) called 941110_UV.cdf containing UV wind data for a series of lat/lon coordinates.

The data file is located in your NCAR Graphics data directory in a subdirectory called "cdf". You can get the name of the data directory by typing "ncargpath data" at your shell prompt. If you have netCDF installed on your system, then you can change directory to where the netCDF file resides and type "ncdump -h 941110_UV.cdf" to view the header information for this data file.

How to run this example

The examples are installed in the following locations:

The netCDF data file is installed in the following location:

You can copy this example and run it by typing "ng4ex cn14c", "ng4ex cn14f", or "ng4ex cn14n". A copy of the source file and resource file will be placed in your current working directory. The source code will be compiled and automatically run for you. You must have the netCDF library installed on your system in order to compile the C or FORTRAN version of this example.

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$Revision: 1.6 $ $Date: 1999/03/23 18:34:18 $