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Discussion Groups | Matlab DSP | ??? Undefined function or variable 's'.

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??? Undefined function or variable 's'. - Zeinab Ghofrani - Jun 18 18:13:00 2004

Hello to all
I have a matrix called A, which contains some numbers. I want to add the symbol s to some of the elements of the matrix and then take the inverse laplace transform of the matrix. but I can't do it. It gives the error below:
??? Undefined function or variable 's'.
Error in ==> D:\MATLAB\toolbox\symbolic\@sym\double.m
On line 45  ==> D = reshape(eval(X),m,n);
Error in ==> D:\MATLAB\work\circuit.m
On line 124  ==>         if m~=0, y(m,m)=y(m,m)+s*element_value,end
The code I use is:
syms s
if m~=0
in which "element_value" and "m" are scalars defined beforehand.
I would appreciate it if somebody helps me.
Zeinab Ghofrani