from symbolic to tf_object
from symbolic to tf_object
(OP)
hi
i have a polynomial expression: Q(s)=4*S^2+1, defined as “symbolic” but I need it as “tf-object” (defined as a transfer function) to be used in the matlab command "lsim", anyone knows how to do it?
thanks
gabi
i have a polynomial expression: Q(s)=4*S^2+1, defined as “symbolic” but I need it as “tf-object” (defined as a transfer function) to be used in the matlab command "lsim", anyone knows how to do it?
thanks
gabi





RE: from symbolic to tf_object
A transfer function is reprented by a numerator polynomial and denominator polynomial. A polynomial is a vector identifying the coefficients from highest order down to 0 order (constant)
For your example:
num = [4 0 1]
den = [1]
lsim(num,den,u,t)
(see help for u,t)
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RE: from symbolic to tf_object
Why do I have Q(s) as a "sym-object"? well, i had to made several previous calculus and as I a have 3 variables y need to define s as symbolic
RE: from symbolic to tf_object
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