IMSL Exponent Graphics: Instructions: C (cc)

Setting the Exponent Graphics Working Environment for C (cc)

To use Exponent Graphics, you must set several UNIX environment variables. These settings may adversely interact with settings needed for other UNIX applications. The instructions below provide a strategy for avoiding these interactions.

You start a new shell before you use IMSL Exponent Graphics, modify the environment, run the programs, and exit the shell before working with other software. You can start a new shell either by opening a new window on an X terminal or by issuing the UNIX csh command. These instructions assume that you are using the C shell (csh), which is the default for University of Delaware users.

Start a new C shell by typing at the C shell prompt (%),

csh

Set the necessary environment variables for Exponent Graphics by typing at the C shell prompt (%),

source /opt/lib/ipt_1.2/ipt/bin/iptsetup.csh

Add the location for the X11 load library by typing at the C shell prompt (%),

setenv LD_LIBRARY_PATH /opt/X11R5/lib:${LD_LIBRARY_PATH}

Define the C compiler's compilation flags to include the X11R5 include directory by typing at the C shell prompt (%),

setenv CFLAGS "$CFLAGS -I/opt/X11R5/include"

Proceed to the compilation and execution steps for your program.

Important warning:

after

consult@udel.edu

Compiling and Executing a C (cc) Program

Compile the C program, using the C compiler options defined above and linking to the Exponent Graphics link library. If your C program is stored in the file filename.c, and you want to store the compiled version in a file named filename, type

cc -o filename filename.c $CFLAGS $LINK_EG

Run the program by typing,

filename

If prompted by the program for an output device, type 1 for the X terminal screen, or type ? to see the other choices.
A complete C example is presented below.

C (cc) Example Programs

confill1.c

Start a new shell by typing,

csh

Set up the working environment as described above.

Use an editor (such as pico or vi) to create a file named example.c containing the following lines.

#include "ac.h"

static double cfill_1(double x, double y);

void main()
{
    int             number_x, number_y;
    double          x_start, x_stop, y_start, y_stop;
    int             new_plot, nval = 5;

    number_x = 11;
    number_y = 11;
    x_start = y_start = -1.0;
    x_stop = y_stop = 1.0;

/*
 * Generate the triangular grid and contours
 */
    if (ac_tgrid_contour_function_plot(cfill_1, number_x, number_y,
                                       x_start, x_stop, y_start, y_stop,
                                       nval,
                                       "no_label",
                                       "contour_fill",
                                       0)) {
        puts(" Error in ac_function_contour_plot\n");
        exit(1);
    } else {
/*
 * Generate 3d version of filled contour plot
 */
        new_plot = ac3_contour_fill(nval, 0);
        ac3_plot(0, 0);
    }
}

static double cfill_1(double x, double y)
{
    double          rval, xval, yval;

    rval = 2.0 - (x * x + y * y);
    return rval;
}

Compile the program and store the compiled version in a file named example by typing,

cc -o example example.c $CFLAGS $LINK_EG

Run the program by typing,

example

When prompted to specify an output device, type 1 to plot on the X terminal. The following graph will appear in a new window.

Click the mouse button in the new graph window to close. Now you are prompted again to specify an output device, type 11 to create a landscape postscript file. You will see the following error

 **** VNI-HOOPS error in ac_Pause has severity 3.
 **** There was an unexpected Hoops internal error -
 **** Nothing to wait for - no events are enabled
 **** Traceback =======>
 ****                   ac_Await_Event
 **** called from       ac_Await_Event
 **** called from       ac_Pause
 **** called from       ac3_plot
 **** called from       ac3_set

A new file is created called vnieg.ps regardless of the above error. You can print this file to any Postscript printer. Again you are prompted to specify an output device, type q to quit.

Instructions:Table of Contents

Main IMSL Exponent Graphics page

[Help Center]

Anita Z. Hoover

URL of this document: http://www.udel.edu/debd/newtemplate/inst1.html