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System object: dsp.FIRInterpolator
Package: dsp

Reset FIR interpolator filter states




reset(H) resets the filter states of the FIR filter in the interpolator object, H, to their initial values of 0. The initial filter state values correspond to the initial conditions for the constant coefficient linear difference equation defining the FIR filter. After the step method applies the interpolator to nonzero input data, the states may be nonzero. Invoking the step method again without first invoking the reset method may produce different outputs for an identical input.

Reset filter states to 0 to produce consistent output:

H = dsp.FIRInterpolator(2);
x =[1 -1]'; x = repmat(x,8,1);
y = step(H,x); % Filter states are nonzero
% Use reset method to set states to zero
% Apply FIR interpolator to input x
y1 = step(H,x);
% Returns a 1
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