The archive file conplot.zip contains the files:
|arc11441.txt||the original program description from COSMIC|
|conplot.f90||the source code in modern Fortran|
|original.src||the original copy of the source code (from COSMIC)|
|test1.f90||a sample program using a function coded in Fortran|
|test2.f90||a sample program that reads data|
|test2dat.txt||some example data for test2|
|test2con.txt||some example contours for the data in test2dat.txt|
The principal items of code are the modules Smooth and Contour. Conplot is not a program, but a module that you use in your programs. I have supplied two programs that let you practice.
test1 plots contours using data points that you compute in the main program. To compile this program, use the command
gfortran test1.f90 -o test1.exe
To launch the program, enter "test1.exe" at the command line. There is no input data. The program makes a file called test.gnu that may be used with gnuplot. For example,
gnuplot>plot 'test.gnu' with lines
To avoid distortion of the image use the plotting command
gnuplot> set size ratio -1
test2 plots contours using data points that are read from a file. The program will ask for the name of this data file. Each line of the input data contains three numbers - x, y, f(x,y). The program reads until there is no more data and then inquires about a file of contour values. This file contains one value per record containing the contour level for each contour line to be plotted. There is a sample case called test2dat.txt that represents the pressure coefficients on a delta wing in supersonic flow. It is taken from NASA TN D-1264 by Harry Carlson. The file called test2con.txt has some contour values that may be used. You can experiment with smoothing and see the change in contours. To begin, try saying that you want smoothing and then try iexp=3 and jexp=4. I am not really sure what these mean, but you might figure it out from the source code.
Test2 also produces a file called test.gnu that may be used with gnuplot as shown above.