NAME¶

ZSCAL - scales a vector by a constant.

SYNOPSIS¶

subroutine zscal(n,za,zx,incx)

c scales a vector by a constant. c jack dongarra, 3/11/78. c modified to correct problem with negative increment, 8/21/90. double complex za,zx(1) integer i,incx,ix,n if(n.le.0)return if(incx.eq.1)go to 20 c code for increment not equal to 1 ix = 1 if(incx.lt.0)ix = (-n+1)*incx + 1 do 10 i = 1,n zx(ix) = za*zx(ix) ix = ix + incx 10 continue return c code for increment equal to 1 20 do 30 i = 1,n zx(i) = za*zx(i) 30 continue return end

PURPOSE¶