how can i standardise the elements in a matrix

I want to standardie the elements in a 9*576 double matrix (pn) in matlab.

I use the below code, but i dont get the same dimension, it gives 9*1 double matrix(pn1) , how can i standardise each element and get the same dimension.

mu = mean(pn);
sig = std(pn);
pn1 = (pn- mu) / sig;

[Star Strider]

I deleted my Answer (originally posted on 3 Dec 2020 at 1:48), since there are extensive repeated posts on the same subject: normalising and reverse normalising data, normalisation and reverse process _Forecasting _mean standard deviation , and perhaps others.

[NN]

I have seen your post and thank you so much.

But still i am searching for the answer and i would like to know where i did mistake

[Star Strider]

My pleasure.