Dear all! Thank to all of you for the answers to my previous questions!
I'm solving the convection equation (see PDE solution problem thread for
details). My equation looks like
eq = TransientTerm() == PowerLawConvectionTerm(convCoeff)
Now I want to add a VARIABLE SOURCE to it. A constant source is
described in manual and works fine. To add a variable source I do the
following:
#define a function that describes my source
def S(x):
E=x
if E>10:
return 5e-7*E**alpha*exp(-E/Ecut)
else:
return 0
#fipy said it wants a CellVariable for the source term
Source = CellVariable(mesh=mesh)
Source.setValue(S(x))
#change the equation:
eq = TransientTerm() == PowerLawConvectionTerm(convCoeff) + Source
Problems/Questions:
1. Is it correct way to introduce the space variable dependent Source to
my problem?
2. I have if/else condition in S(x) function. The script works without
if/else with no errors, but with condition the following error appears:
File "conv_s_1208.py", line 59, in <module>
Source.setValue(S(x))
File "conv_s_1208.py", line 48, in S
if E>10:
ValueError: The truth value of an array with more than one element is
ambiguous. Use a.any() or a.all()
It seems that S(x) gets the whole array of x values of the mesh and in
this case can't compare. Originally I wouldn't like that S(x) function
was designed to take an array argument.
Shouldn't the setValue method take care of it? (i.e. if the function is
written for the scalar argument and an array x[] is passed, setValue
should make a new array where y[i]=S(x[i]). This new array will be then
the Source term.)
If setValue method can't take care of it, is there a way to overcome
this difficulty and do not change S(x) function?
Is there a way in python to check what object (array, float ...) is a
passed to the function as an argument?
Thanks to everybody for the answers!
