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Scales a vector by a constant.

Usage

dscal(N = NULL, ALPHA, Y, INCY = 1L)

Arguments

N

an integer. Number of elements in input vector(s)

ALPHA

a real number. The scalar alpha

Y

a big matrix to scale by ALPHA

INCY

an integer. Storage spacing between elements of Y.

Value

Update Y.

Examples

set.seed(4669)
A = big.matrix(3, 2, type="double", init=1, dimnames=list(NULL, 
c("alpha", "beta")), shared=FALSE)
dscal(ALPHA=2,Y=A)
#> An object of class "big.matrix"
#> Slot "address":
#> <pointer: 0x151f709d0>
#> 
A[,]
#>      alpha beta
#> [1,]     2    2
#> [2,]     2    2
#> [3,]     2    2

# The big.matrix file backings will be deleted when garbage collected.
rm(A)
gc()
#>           used (Mb) gc trigger  (Mb) limit (Mb) max used  (Mb)
#> Ncells 1146685 61.3    2286118 122.1         NA  2286118 122.1
#> Vcells 2054227 15.7    8388608  64.0      65536  5285191  40.4