array.mult {fastmatrix} | R Documentation |
Array multiplication
Description
Multiplication of 3-dimensional arrays was first introduced by Bates and Watts (1980). More extensions and technical details can be found in Wei (1998).
Usage
array.mult(a, b, x)
Arguments
a |
a numeric matrix. |
b |
a numeric matrix. |
x |
a three-dimensional array. |
Details
Let be a 3-dimensional
where
indices
and
indicate face, row and column, respectively. The
product
is an
array, with
and
are
and
matrices
respectively. The elements of
are defined as:
Value
array.mult
returns a 3-dimensional array of dimension .
References
Bates, D.M., Watts, D.G. (1980). Relative curvature measures of nonlinearity. Journal of the Royal Statistical Society, Series B 42, 1-25.
Wei, B.C. (1998). Exponential Family Nonlinear Models. Springer, New York.
See Also
Examples
x <- array(0, dim = c(2,3,3)) # 2 x 3 x 3 array
x[,,1] <- c(1,2,2,4,3,6)
x[,,2] <- c(2,4,4,8,6,12)
x[,,3] <- c(3,6,6,12,9,18)
a <- matrix(1, nrow = 2, ncol = 3)
b <- matrix(1, nrow = 3, ncol = 2)
y <- array.mult(a, b, x) # a 2 x 2 x 2 array
y
[Package fastmatrix version 0.5-772 Index]