Macro Draw 2D Function

Use it to draw a function described by a "equation" [z=F(x)] (Z-X plane) The example done here generate a parabol.
Has no dialog. Needs to be defined :
F = variable used in the function,
X = initial value of x,
Nb = Number of step,
Z = function express with x
ZZ = function express with xx

# F = variable used in the function,
# X = initial value of x,
# Nb = Number of step,
# Z = function express with x
# ZZ = function express with xx

import FreeCAD, FreeCADGui, Part
import math
F=800
X=-500
Nb=10
Step=1000/Nb
Y=0
for I in range(Nb):
XX=X+Step 
 Z=X*X/(4*F)
 ZZ=XX*XX/(4*F)
 if I==0:
 print "Le test est vrai !"
 nomme=Part.makeLine((X,Y,Z),(XX,Y,ZZ))
 WWire=Part.Wire([nomme])
 else :
 print "Le test est 2 !"
 nomme=Part.makeLine((X,Y,Z),(XX,Y,ZZ))
 WWire=Part.Wire([WWire,nomme])
 X=XX 
 
Part.show(WWire)