validstructures - Structures for specification object with design method
Syntax
validstructures(d)
validstructures(d,'designmethod')
c = validstructures(d,'designmethod')
Description
validstructures(d) returns the list of
structures for all design methods that are available for d.
validstructures(d,'designmethod') returns
a list of the filter structures available for the specification object d and
the design method in designmethod. Knowing which
structures apply to your combination of design method and specification
makes deciding on a filter structure to implement easier.
To determine the available structures, validstructures considers
the filter response, such as lowpass or bandstop. It also considers
the specifications you use to define the response, such as filter
order or stopband attenuation, because changing the filter specifications
often changes the available structures.
c = validstructures(d,'designmethod') returns
the output cell array c that contains the filter
structures as character strings.
Examples
Design a default lowpass fillter specification object and query
all valid structures by design method.
d=fdesign.lowpass;
validstructures(d)
ans =
butter: {'df1sos' 'df2sos' 'df1tsos' 'df2tsos'}
cheby1: {'df1sos' 'df2sos' 'df1tsos' 'df2tsos'}
cheby2: {'df1sos' 'df2sos' 'df1tsos' 'df2tsos'}
ellip: {'df1sos' 'df2sos' 'df1tsos' 'df2tsos'}
equiripple: {'dffir' 'dffirt' 'dfsymfir' 'fftfir'}
kaiserwin: {'dffir' 'dffirt' 'dfsymfir' 'fftfir'}
Create a highpass filter of order 50 with a 3–dB frequency
of 0.2.
d=fdesign.highpass('N,F3dB',50,0.2);
validmethod=designmethods(d) %check valid design methods
validmethod
validmethod =
'butter'
%Butterworth is the only valid design
validstructures(d,'butter') %check valid structures
ans =
'df1sos' 'df2sos' 'df1tsos' 'df2tsos'See Also
design, designopts.
 | upsample | | vco |  |
Includes the most popular MATLAB recorded presentations with Q&A sessions led by MATLAB experts.
Get the Interactive Kit
Store 
