Valid input arguments and values for specification object and method
OPTS = designopts(D,METHOD)
OPTS = designopts(D,METHOD) returns
a structure array with the default design parameters used by the design
METHOD must be
one of the options returned by
help(D,METHOD) to get a description
of the design parameters.
If you have DSP System Toolbox™ software installed,
SystemObject property if at least one of
the structures available for that design method is supported by System
objects. However, not all structures for that design method are supported
by System objects.
Create a lowpass filter with a numerator and denominator order of 10 and a 3-dB frequency of 0.2π radians/sample. Obtain the default design parameters for a Butterworth design, and test whether the filter structure is a direct-form II biquad.
D = fdesign.lowpass('Nb,Na,F3dB',10,10,0.2); OPTS = designopts(D,'butter'); if (OPTS.FilterStructure == 'df2sos') fprintf('The default filter structure is Direct-Form II\n'); fprintf('with second-order sections.\n'); end
If you have DSP System Toolbox software installed,