%% Lowpass FIR Filter in Single and Double Precision
% Use designfilt to design a 5th-order FIR lowpass filter. Specify a normalized passband frequency of 0.2\pi rad/sample and a normalized stopband frequency of 0.55\pi rad/sample.
% Cast the filter to single precision and cast it back to double precision. Display the first coefficient of each filter.

format long
d = designfilt('lowpassfir','FilterOrder',5, ...
               'PassbandFrequency',0.2,'StopbandFrequency', 0.55);
e = single(d);
f = double(e);

coed = d.Coefficients(1)
coee = e.Coefficients(1)
coef = f.Coefficients(1)

% Use double to analyze, in double precision, the effects of single-precision quantization of filter coefficients.
% Copyright 2015 The MathWorks, Inc.