Issue creating a probability density function for audio file

Hello. Thank you in advance.

I want to generate probability density functions of amplitudes from audiofiles. However, when I use the pdf function, I get a vector of NaNs, and I do not know why. It seems to me it should be a very simple code, so I am not sure what I am missing here. See below.

[f,fs] = audioread('sound_file.wav'); %read in audio
x = sum(f,2); %average 2 channels to get single vector
y = pdf('Normal',x); %get PDF values

Answer 1

[Walter Roberson]

Normal distribution expects two parameters, the mean and the standard deviation. The defaults for those parameters are both 0, so Normal distribution with 0 mean and 0 standard deviation. But 0 standard deviation on a normal distribution leads to NaN for all values.

[Erik J]

Ah, thank you.