direct.prod: Direct prod of two arrays

In matrixcalc: Collection of Functions for Matrix Calculations

Direct prod of two arrays

Description

This function computes the direct product of two arrays. The arrays can be numerical vectors or matrices. The result is a matrix.

Usage

direct.prod( x, y )

Arguments

x	a numeric matrix or vector
y	a numeric matrix or vector

Details

If either \bf{x} or \bf{y} is a vector, it is converted to a matrix. Suppose that \bf{x} is an m \times n matrix and \bf{y} is an p \times q matrix. Then, the function returns the matrix ≤ft\lbrack {\begin{array}{cccc} {{x_{1,1}}\;{\bf{y}}}&{{x_{1,2}}\;{\bf{y}}}& \cdots &{{x_{1,n}}\;{\bf{y}}}\\ {{x_{2,1}}\;{\bf{y}}}&{{x_{2,2}}\;{\bf{y}}}& \cdots &{{x_{2,n}}\;{\bf{y}}}\\ \cdots & \cdots & \cdots & \cdots \\ {{x_{m,1}}\;{\bf{y}}}&{{x_{m,2}}\;{\bf{y}}}& \cdots &{{x_{m,n}}\;{\bf{y}}} \end{array}} \right\rbrack.

Value

A numeric matrix.

Author(s)

Frederick Novomestky [e-mail], Kurt Hornik [e-mail]

References

Magnus, J. R. and H. Neudecker (1999) Matrix Differential Calculus with Applications in Statistics and Econometrics, Second Edition, John Wiley.

Examples

x <- matrix( seq( 1, 4 ) )
y <- matrix( seq( 5, 8 ) )
print( direct.prod( x, y ) )

matrixcalc documentation built on Sept. 15, 2022, 1:05 a.m.