gdata (version 2.7.1)

upperTriangle: Extract or replace the upper/lower triangular portion of a matrix

Description

Extract or replace the upper/lower triangular portion of a matrix

Usage

upperTriangle(x, diag=FALSE)
upperTriangle(x, diag=FALSE) <- value
lowerTriangle(x, diag=FALSE)
lowerTriangle(x, diag=FALSE) <- value

Arguments

x

Matrix

diag

Logical. If TRUE, include the matrix diagonal.

value

Either a single value or a vector of length equal to that of the current upper/lower triangular. Should be of a mode which can be coerced to that of x.

Value

• upperTriangle(x) and lowerTriangle(x) return the upper or lower triangle of matrix x, respectively. The assignment forms replace the upper or lower traingular area of the matrix with the provided value(s).

See Also

diag

Examples

x <- matrix( 1:25, nrow=5, ncol=5)
  x
  upperTriangle(x)
  upperTriangle(x, diag=TRUE)

  lowerTriangle(x)
  lowerTriangle(x, diag=TRUE)

  upperTriangle(x) <- NA
  x

  upperTriangle(x, diag=TRUE) <- 1:15
  x

  lowerTriangle(x) <- NA
  x

  lowerTriangle(x, diag=TRUE) <- 1:15
  x