Rescale: Difference between revisions

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:rx = rescale(x,means,stds,options)
:rx = rescale(x,means,stds,options)
:rx = rescale(x,means)


===Description===
===Description===


Rescales a matrix <tt>x</tt> using the means <tt>means</tt> and standard deviation <tt>stds</tt> vectors specified.
Rescales a matrix <tt>x</tt>, using the means <tt>means</tt> and standard deviation <tt>stds</tt> vectors specified.


====Inputs====
====Inputs====
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* '''stds''' = vector of standard deviations to be used for rescaling
* '''stds''' = vector of standard deviations to be used for rescaling


If only two input arguments are supplied the function corrects the means only.
If only two input arguments are supplied, the function will correct the means only.


====Outputs====
====Outputs====
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===Examples===
===Examples===


:rx = rescale(x,means) rescales a mean centered matrix <tt>x</tt> using a vector of means <tt>means</tt>.
rx = rescale(x,means)
rescales a mean centered matrix <tt>x</tt> using a vector of means <tt>means</tt>.


:rx = rescale(x,means,stds) rescales a previously autoscaled matrix <tt>x</tt> using a vector of means <tt>means</tt>, and vector of standard deviations <tt>stds</tt>.
rx = rescale(x,means,stds)
rescales a previously autoscaled matrix <tt>x</tt> using a vector of means <tt>means</tt>, and vector of standard deviations <tt>stds</tt>.


===See Also===
===See Also===


[[auto]], [[medcn]], [[mncn]], [[npreprocess]], [[preprocess]], [[scale]]
[[auto]], [[medcn]], [[mncn]], [[npreprocess]], [[preprocess]], [[scale]]

Latest revision as of 15:54, 22 February 2013

Purpose

Scales data back to original scaling.

Synopsis

rx = rescale(x,means,stds,options)
rx = rescale(x,means)

Description

Rescales a matrix x, using the means means and standard deviation stds vectors specified.

Inputs

  • x = matrix of input data
  • means = vector of means to be used for rescaling
  • stds = vector of standard deviations to be used for rescaling

If only two input arguments are supplied, the function will correct the means only.

Outputs

  • rx = rescaled version of the input data x

Options

options = a structure array with the field:

  • stdthreshold = [0] scalar value or vector of standard deviation threshold values. If a standard deviation is below its corresponding threshold value, the threshold value will be used in lieu of the actual value. A scalar value is used as a threshold for all variables.

Examples

rx = rescale(x,means)

rescales a mean centered matrix x using a vector of means means.

rx = rescale(x,means,stds)

rescales a previously autoscaled matrix x using a vector of means means, and vector of standard deviations stds.

See Also

auto, medcn, mncn, npreprocess, preprocess, scale