Help normalizing data in table

data=table(10*randn(100,1)+5, randn(100,1)/10, randn(100,1).^2);
ndata = data(:,1:3);
ndata{:,1:3} = normalize(ndata{:,1:3});
round(mean(table2array(ndata)),-10)
ans = 1×3
     0     0     0
std(table2array(ndata))
ans = 1×3
    1.0000    1.0000    1.0000

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Dave B 2021-12-3

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For the round bit - that's just because (after normalizing) the mean is close to zero, but not exactly zero. I rounded it to 10 digits. Here's what it looks like without the round:

data=table(10*randn(100,1)+5, randn(100,1)/10, randn(100,1).^2);
ndata = data(:,1:3);
ndata{:,1:3} = normalize(ndata{:,1:3});
mean(table2array(ndata))
ans = 1×3
	1.0e+-15 *

   -0.0844    0.0266   -0.1821

So that's like -0.0000000000000000844 for the first one (I might have miscounted my zeros!)

I'm not sure what you mean by the std is not 1, can you give an example? (similar to the means, they're not exactly 1, but I'd think would be close to 1). Note that you can also use zscore in place of normalize, I just wanted to help with the 'how to apply it to table' bit...but I'd expect zscore and normalize to produce the same results...

Nina Perf 2021-12-3