Problem with pdeInterpolant matlab function

Hello, I am trying to interpolate the logarithm of a solution of an EDP using the matlab pdeInterpolant function, but I get the following error message:

Error using pdeInterpolant

Argument "u" contains values that are not valid doubles.

Error in Test13 (line 13)

F = pdeInterpolant(p,t,log(abs(u)));

I have attached the code I was using here.

Can someone help me please.