MATLAB: Generating random variable from certain standard deviation and mean

random variable

Could you please help me how can I generate random variable from Gaussian distribution with zero mean and 0.3 standard deviation?

a = .3;%  standard deviation
b = 0; %  mean
out = a.*randn + b;

numdev = floor((mean(S)-min(S))./std(S));

Determining the position of each standard deviation and plotting is left as a homework exercise.

Though possibly you want

numdev = floor((mean(S,2)-min(S,[],2))./std(S,[],2));

If you want normally-distributed random numbers with zero mean and unit variance (and therefore unit standard deviation), use the randn function:

N01 = randn(1,10);

This will generate a 10-element row vector with zero mean and unit variance.