scalewt {ade4}R Documentation

Centring and Scaling a Matrix of Any Weighting

Description

transforms a numeric matrix in a centred and scaled matrix for any weighting.

Usage

scalewt(X, wt = rep(1, nrow(X)), center = TRUE, scale = TRUE)

Arguments

X a numeric matrix (like object)
wt a vector of weighting
center a logical value indicating whether the array should be centred
scale a logical value indicating whether the array should be scaled

Value

returns a centred, scaled matrix

Note

The norms are calculated with 1/n and the columns of null variance are still equal to zero.

Author(s)

Daniel Chessel

Examples

scalewt(matrix(1:12,4,3))
scale((matrix(1:12,4,3)))
scale(matrix(1,4,3))
scalewt(matrix(1,4,3))

Worked out examples


> library(ade4)
> ### Name: scalewt
> ### Title: Centring and Scaling a Matrix of Any Weighting
> ### Aliases: scalewt
> ### Keywords: utilities
> 
> ### ** Examples
> 
> scalewt(matrix(1:12,4,3))
           [,1]       [,2]       [,3]
[1,] -1.3416408 -1.3416408 -1.3416408
[2,] -0.4472136 -0.4472136 -0.4472136
[3,]  0.4472136  0.4472136  0.4472136
[4,]  1.3416408  1.3416408  1.3416408
> scale((matrix(1:12,4,3)))
           [,1]       [,2]       [,3]
[1,] -1.1618950 -1.1618950 -1.1618950
[2,] -0.3872983 -0.3872983 -0.3872983
[3,]  0.3872983  0.3872983  0.3872983
[4,]  1.1618950  1.1618950  1.1618950
attr(,"scaled:center")
[1]  2.5  6.5 10.5
attr(,"scaled:scale")
[1] 1.290994 1.290994 1.290994
> scale(matrix(1,4,3))
     [,1] [,2] [,3]
[1,]  NaN  NaN  NaN
[2,]  NaN  NaN  NaN
[3,]  NaN  NaN  NaN
[4,]  NaN  NaN  NaN
attr(,"scaled:center")
[1] 1 1 1
attr(,"scaled:scale")
[1] 0 0 0
> scalewt(matrix(1,4,3))
     [,1] [,2] [,3]
[1,]    0    0    0
[2,]    0    0    0
[3,]    0    0    0
[4,]    0    0    0
> 
> 
> 
>
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