How to write a for loop to obtain z-scores

Question

mcm 2016-11-2

评论： Star Strider 2016-11-2

Although matlab has a built in z-score function, I need to create a for loop that would do the same thing. How do I improve my code

load('data1');

data1_mean = mean(data1); data1_std = std(data1);

[r,c] = size(data1);

for i = 1:r %Data1 is 50x1 so we need the loop to evaluate for all 50 rows x = (i - data1_mean ./ data1_std; end disp(x)

Answer 1

Star Strider 2016-11-2

You likely can do away with the loop entirely and just use vectorised code:

data1_mean = mean(data1);
data1_std = std(data1);
x = (data1 - data1_mean)./data1_std;

mcm 2016-11-2

I am aware of that, but what if I want to use a for loop to achieve the same result?

Star Strider 2016-11-2

That’s straightforward:

for k1 = 1:length(data1)
    x(k1) = (data1(k1) - data1_mean)./data1_std;
end

That’s how I would do it.

NOTE — This is UNTESTED CODE but should work.