@colstdize |

Standardize each column using the sample standard deviation.

Syntax: @colstdize(m)

m: matrix, vector

Return: matrix, vector

Returns the matrix containing the results from standardizing each column of m.

For each element of the output:

for the mean and the sample (d.f. corrected) standard deviation of column where

(18.2) |

where is the number of non-missing values in the column. If there are missing values in a column, they are ignored and the number of rows is adjusted.

Examples

matrix m1 = @mnrnd(50, 4)

matrix m1s = @colstdize(m1)

standardizes each column of M1 and places the results in M1D.

This operation is equivalent to

vector m1means = @cmeans(m1)

vector m1stds = @cstdev(m1)

matrix temp = m1 - @kronecker(@ones(m1.@rows), m1means.@t)

matrix m2s = @scale(temp, m1stds.@t)

where @cmeans and @cstdev is used to compute the column means and sample standard deviations of M1.

Cross-references

See also
@colstdizep, and
@coldemean.