doublemean: Double mean matrix

In svdvisual: SVD visualization tools

Description

This function returns the double mean matrix of an input matrix

Usage

  doublemean(x)

Arguments

x	The input matrix. Make sure this is a matrix object

Details

This function calculates the mean of each row, each column and the overall mean within the input matrix. If the matrix has dimension m x n, this function will return a m x n matrix, where each cell is the sum of the row mean and the column mean, subtract by the overall mean.

Let X be the m \times n input matrix, x_{ij} is the i, j cell within it. Let D be the resulting matrix of this program, and d_{ij} as the corresponding cell. Let

r_i =\frac{1}{n}∑_{j=1}^n x_{ij}, c_j=\frac{1}{m}∑_{i=1}^m x_{ij}, o=\frac{1}{mn}∑_{i=1}^m∑_{j=1}^n x_{ij}.

Then

d_{ij}=r_i+c_j-o;

Value

The double mean matrix

Author(s)

Yao Wang ([e-mail]); Lingsong Zhang ([e-mail])

See Also

See Also in svd, apply, columnmean, rowmean, overallmean.

Examples

#generate a random matrix
x<-matrix(rnorm(100), nrow=20);

#calculate the row mean matrix
y<-doublemean(x);
y

svdvisual documentation built on May 2, 2019, 4:15 a.m.