dsp.ZeroCrossingDetector: a confusing error

Question

parham kianian 2020-4-9

回答： Mehmed Saad 2020-4-9

I am trying to employ dsp.ZeroCrossingDetector to count number of zero crossings of a signal. Consider the following:

x = 0 : pi/180 : 4*pi;
y = sin(x);
zcd = dsp.ZeroCrossingDetector;
n = zcd(y);
release(zcd);

It is expected that size of n be 1*1, that is a sclar, but MATLAB returns n as vector of zeros with the same size as x.

How can I solve this problem?

Answer 1

Mehmed Saad 2020-4-9

dsp.ZeroCrossingDetector needs column vector as an input while you are feeding it a row vector

take transpose of x

x = (0 : pi/180 : 4*pi).'; %Transpose it(.')
y = sin(x);
zcd = dsp.ZeroCrossingDetector;
n = zcd(y);
release(zcd);

dsp.ZeroCr​ossingDete​ctor: a confusing error