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Scilab help >> Statistics > wcenter

# wcenter

center and weight

### Calling Sequence

```s=wcenter(x)
s=wcenter(x,'r') or s=wcenter(x,1)
s=wcenter(x,'c') or s=wcenter(x,2)```

### Arguments

x: real or complex vector or matrix

### Description

This function computes `s`, the weigthed and centred version of the numerical matrix `x`.

For a vector or a matrix `x`, `s=wcenter(x)` returns in the `(i,j)` coefficient of the matrix `s` the value `(x(i,j)-xbar)/sigma`, where `xbar` is the mean of the values of the coefficients of `x` and `sigma` his standard deviation.

`s=wcenter(x,'r')` (or, equivalently, `s=wcenter(x,1)`) is the rowwise centre reduction of the values of `x`. It returns in the entry `s(i,j)` the value `(x(i,j)-xbarv(j))/sigmav(j)` with `xbarv(j)` the mean of the values of the `j` column and `sigmav(j)` the standard deviation of the `j` column of `x`.

`s=wcenter(x,'c')` (or, equivalently, `s=wcenter(x,2)`) is the columnwise centre reduction of the values of `x`. It returns in the entry `s(i,j)` the value `(x(i,j)-xbarh(i))/sigmah(i)` with `xbarh(i)` the mean of the values of the `i` row and `sigmah(i)` the standard deviation of the `i` row of `x`.

### Examples

```x=[0.2113249 0.0002211 0.6653811;
0.7560439 0.3303271 0.6283918]
s=wcenter(x)
s=wcenter(x,'r')
s=wcenter(x,'c')```

Carlos Klimann