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+--- Thread: [SOLVED] Issue with cZeros (/thread-7721.html)
[SOLVED] Issue with cZeros - tiamattia - 02-05-2017 11:06 AM
Hello,
I'm developing a program to design filters using Butterworth and Chebyshev type I. To do this i defined some cas function to solve equations or denormalize things. Some of these functions are:
Code:
BP_Denorm_TF(n_filter_gain, n_filter_poles, w_central, filter_q_factor) :=
BEGIN
cFactor(normal(n_filter_gain/ poly2symb(pcoeff(n_filter_poles), filter_q_factor * (x ^ 2 + w_central ^ 2) / (w_central * x)))); // BP transfer function
END;
BP_Denorm_Zeros(n_filter_gain, n_filter_poles, w_central, filter_q_factor) :=
BEGIN
cZeros(BP_Denorm_TF(n_filter_gain, n_filter_poles, w_central, filter_q_factor));
END;BP_Denorm_TF works right also inside of a program.
Instead, BP_Denorm_Zeros is not working as it should inside of a program.
If i call this function directly from cas, everything works, the result is two zeros in the origin.
If i call this function inside of a program, no solutions are returned.
What's the problem?
RE: Issue with cZeros - tiamattia - 02-05-2017 11:31 AM
Problem solved, when using CAS commands in program mode, you have to provide the variable to solve. I think it's because in program mode the default var is X while in CAS is x. (I'm usign x)