python - PyLab contourf with experimental data -

i'm trying understand , adapt following code:

import numpy np  def f(x,y):     return (1 - x / 2 + x**5 + y**3) * np.exp(-x**2 -y**2)  n = 256 x = np.linspace(-3, 3, n) y = np.linspace(-3, 3, n) x,y = np.meshgrid(x, y)  pl.axes([0.025, 0.025, 0.95, 0.95])  pl.contourf(x, y, f(x, y), 8, alpha=.75, cmap=pl.cm.hot) c = pl.contour(x, y, f(x, y), 8, colors='black', linewidth=.5) pl.clabel(c, inline=1, fontsize=10)  pl.xticks(()) pl.yticks(()) pl.show() 

here have set of points (x,y) , value each point, computed f(x,y)

now, have set of computational results in form of x;y;output in txt output file read csv module example. point i'm not understanding data types here, meshgrid. let's each point key key in dictionary fh_dict fh_dict[key] play role of f(x,y) in code above. don't know how implement it, output value each point not easy express mathematical function.

thanks time.