30 lines
684 B
Fortran
30 lines
684 B
Fortran
subroutine zdscalf(n,da,zx,incx)
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c
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c scales a vector by a constant.
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c jack dongarra, 3/11/78.
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c modified 3/93 to return if incx .le. 0.
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c modified 12/3/93, array(1) declarations changed to array(*)
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c
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double complex zx(*)
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double precision da
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integer i,incx,ix,n
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c
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if( n.le.0 .or. incx.le.0 )return
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if(incx.eq.1)go to 20
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c
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c code for increment not equal to 1
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c
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ix = 1
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do 10 i = 1,n
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zx(ix) = dcmplx(da,0.0d0)*zx(ix)
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ix = ix + incx
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10 continue
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return
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c
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c code for increment equal to 1
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c
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20 do 30 i = 1,n
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zx(i) = dcmplx(da,0.0d0)*zx(i)
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30 continue
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return
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end
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