xxt {KRIS}

Calculate matrix multipication between a matrix and its transpose for large data.

Description

Calculate matrix multiplication using "divide and conquer technique", which accelerates the computation to be faster.

Usage

xxt(X, window.size = 5)

Arguments

X

An input matrix to be processed.

window.size

The window size of matrices to be devided. The default value is 5.

Value

The multiplication matrix of X.t(X).

Examples

#Use the example files embedded in the package.
X <-matrix(runif(100), ncol=20)
R1  <- xxt(X)

#Show the result (R1)
print(R1)
R2 <- X %*% t(X)

#Show the result (R2)
print(R2)