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Determine if digital filter coefficients are double precision



flag = isdouble(d) returns true if the coefficients of a digital filter, d, are double precision.


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Use designfilt to design a sixth-order highpass IIR filter. Specify a normalized passband frequency of 0.6π rad/sample. Convert it to a single-precision filter. Identify the precision in each case.

fd = designfilt('highpassiir','FilterOrder',6,'PassbandFrequency',0.6);
isd = isdouble(fd)
isd = logical

fs = single(fd);
iss = isdouble(fs)
iss = logical

Input Arguments

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Digital filter, specified as a digitalFilter object. Use designfilt to generate d. If you want a single-precision filter, apply single to the output of designfilt.

Example: d = designfilt('lowpassiir','FilterOrder',3,'HalfPowerFrequency',0.5) specifies a third-order Butterworth filter with normalized 3-dB frequency 0.5π rad/sample.

Output Arguments

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Type identification, returned as a logical scalar.

Version History

Introduced in R2014a