PLS_Toolbox Documentation: auto	< areadr	autocor >

auto

Purpose

Autoscales a matrix to mean zero and unit variance.

Synopsis

[ax,mx,stdx,msg] = auto(x,options)

[ax,mx,stdx,msg] = auto(x,offset)

options = auto('options')

Description

[ax,mx,stdx] = auto(x) autoscales a matrix x and returns the resulting matrix ax that has columns with mean zero and unit variance. Output mx is a vector of means, and stdx is a vector of standard deviations. mx and stdx can be used to scale new data (see SCALE).

Options

             options =   a structure array with the following fields:

                     name:   'options', name indicating that this is an options structure,

                 offset:   scaling can use standard deviation plus an offset {default = 0},

               display:   [ {'off'}| 'on' ] governs level of display to the command window,

matrix_threshold:      fraction of missing data allowed based on entire matrix (x) {default = 0.15}, and

column_threshold:      fraction of missing data allowed base on a single column {default = 0.25}.

The optional input offset is added to the standard deviations before scaling and can be used to suppress low-level variables that would otherwise have standard deviations near zero.

The default options can be retreived using: options = auto('options');.

See Also

gscale, medcn, mncn, normaliz, npreprocess, regcon, rescale, scale, snv