NCL > Application examples > Basic examples

XyPlot example 7

Creating a scattergram

This example can be created using HLU C library calls, HLU FORTRAN library calls, or NCL. This example demonstrates how to create a "scattergram" using the XyPlot utility. The names of the source files for this example are xy07c.c, xy07f.f, xy07n.ncl.


This module discusses how to create this plot using HLU function calls and NCL. A resource file is included with this example, and it is called xy07.res. This file is used to change the default resource settings for the plot.

This example is similar to the ncargex Autograph example "agex11". It shows how to draw a "scattergram". It also shows one way to modify the color map to produce different background/foreground colors.

A detailed discussion of how this example works appears in its source code.

Creating the plot using HLUs

The HLU C program that generates this plot is called xy07c.c.

Creating the plot using HLU FORTRAN library calls

The HLU FORTRAN program that generates this plot is called xy07f.f.

Creating the plot using NCL

The NCL script that generates this plot is called xy07n.ncl.

The data

The data for this plot is generated internally by the program code.

How to run this example

The examples are installed in the following locations:

  • $NCARG_ROOT/lib/ncarg/hluex/xyplot/xy07c.c
  • $NCARG_ROOT/lib/ncarg/hluex/xyplot/xy07f.f
  • $NCARG_ROOT/lib/ncarg/nclex/xyplot/xy07n.ncl
The resource file for this example is located in:

  • $NCARG_ROOT/lib/ncarg/resfiles/xyplot/xy07.res
You can copy this example and run it by typing "ng4ex xy07c", "ng4ex xy07f", "ng4ex xy07n". A copy of the source file and resource file will be placed in your current working directory. The source code will be compiled (if necessary) and automatically run for you.