Snv

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Purpose

Standard Normal Variate scaling.

Synopsis

[xcorr,mns,sds] = snv(x,options); %perform snv scaling
x = snv(xcorr,mns,sds); %undo snv

Description

Scales rows of the input x to be mean zero and unit standard deviation. This is the same as autoscaling the transpose of x. INPUT:

  • x = M by N matrix of data to be scaled (class "double" or "dataset").

OPTIONAL INPUTS:

  • options = options structure passed to function "auto" when performing SNV scaling. See auto.m for available options (not valid for undo operation).
  • mns = a vector of length M of means, and
  • sds = vector of length M of standard deviations.

OUTPUTS:

  • xcorr = the scaled data (xcorr will be the same class as x),
  • mns = vector of means for each row, and
  • sds = vector of standard deviations for each row.

To rescale or "undo" SNV, inputs are xcorr, mns, and sds from a previous SNV call. The output will be the original x.

See Also

auto, normaliz, preprocess