center

Arguments

x

real or complex vector or matrix

orientation

index of the dimension along which the center is computed. It can be either

• a character "*" (default), "r" or "c"
• a positive integer: 1 or 2. 1 is equivalent to "r" and 2 is equivalent to "c".

s

real or complex scalar or vector

Description

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

For a vector or a matrix x, s = center(x) or s = center(x, "*") returns in the (i,j) coefficient of the matrix s the value (x(i,j)-xbar), where xbar is the mean of the values of the coefficients of x.

s = center(x, 'r') (or, equivalently, s = center(x, 1)) is the rowwise center reduction of the values of x. It returns in the entry s(i,j) the value x(i,j)-xbarv(j) with xbarv(j) the mean of the values of the j column.

s = center(x, 'c') (or, equivalently, s = center(x, 2)) is the columnwise center reduction of the values of x. It returns in the entry s(i,j) the value x(i,j)-xbarh(i) with xbarh(i) the mean of the values of the i row.

Examples

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

See also

• wcenter — center and weight