Python script "y.py"

Not mandatory, but useful: A Python script which allows to plot two curves. Assume our C-program produces output in the form of three columns, representing two curves (which we want to compare). The first column represents the common x-values of the two curves.

First create (just once) a file called "y.py", with the following content:


#!/usr/bin/python                                       

import matplotlib.pyplot as plt;                        

from pylab import genfromtxt;                           

xx = genfromtxt("out");                                 

plt.plot(xx[:,0], xx[:,1], label = "data 1");           

plt.plot(xx[:,0], xx[:,2], "bs" ,label = "data 2");     

plt.xlabel('x variable')                                

plt.ylabel('y variable')                                

plt.legend();                                           

plt.show();

Run the C-program, which creates the three columns, but do not print on the screen, but into a file called "out", via


a.out > out

Execute the python script via


python y.py

Which will plot the two curves.