bigalgebra (version 1.1.2)

dcopy: Copy a vector.

Description

Copy double precision DX to double precision DY. For I = 0 to N-1, copy DX(LX+I*INCX) to DY(LY+I*INCY), where LX = 1 if INCX .GE. 0, else LX = 1+(1-N)*INCX, and LY is defined in a similar way using INCY.

Usage

dcopy(N = NULL, X, INCX = 1, Y, INCY = 1)

Value

DY copy of vector DX (unchanged if N .LE. 0)

Arguments

N

number of elements in input vector(s)

X

double precision vector with N elements

INCX

storage spacing between elements of DX

Y

double precision vector with N elements

INCY

storage spacing between elements of DY

References

C. L. Lawson, R. J. Hanson, D. R. Kincaid and F. T. Krogh, Basic linear algebra subprograms for Fortran usage, Algorithm No. 539, Transactions on Mathematical Software 5, 3 (September 1979), pp. 308-323.

Examples

if (FALSE) {
set.seed(4669)
A = big.matrix(3, 2, type="double", init=1, dimnames=list(NULL, 
c("alpha", "beta")), shared=FALSE)
B = big.matrix(3, 2, type="double", init=0, dimnames=list(NULL, 
c("alpha", "beta")), shared=FALSE)

dcopy(X=A,Y=B)
A[,]-B[,]

# The big.matrix file backings will be deleted when garbage collected.
rm(A,B)
gc()
}