I am doing some testing with filters in python. Already done it in matlab. When doing so I get different results for the same filter when using impz in matlab and scipy.signal.impulse2 in python. Matlab impz: And this is the result of the python implementation. To have the same I use this in both matlab and python for filter coefficents.

b = np.array([0.0335718093676408, 0, -0.0671436187352817, 0, 0.0335718093676408])
a = np.array([1,-1.74768237925094,2.19561759706246,-1.29097205253115,0.553269889688682])

And matlab code for doing this is just (this also creates the plot in matlab livescript):

impz(b,a)

The python code I have used is this:

T, yout = scipy.signal.impulse2((b,a))

and plot with:

plt.plot(T, yout)

I cant find anything in the docs that says that these should behave so differently

CodePudding user response：

impz and impulse2 are not the same function. impz deals with discrete time systems while impulse2 deals with a continous time system, the equivalent to impz is actully