36 lines
857 B
Fortran
36 lines
857 B
Fortran
REAL*8 function daminf(n,dx,incx)
|
|
c
|
|
c finds the index of element having min. absolute value.
|
|
c jack dongarra, linpack, 3/11/78.
|
|
c modified 3/93 to return if incx .le. 0.
|
|
c modified 12/3/93, array(1) declarations changed to array(*)
|
|
c
|
|
double precision dx(*)
|
|
integer i,incx,ix,n
|
|
c
|
|
daminf = 0
|
|
if( n.lt.1 .or. incx.le.0 ) return
|
|
|
|
if(incx.eq.1)go to 20
|
|
c
|
|
c code for increment not equal to 1
|
|
c
|
|
ix = 1
|
|
daminf = dabs(dx(1))
|
|
ix = ix + incx
|
|
do 10 i = 2,n
|
|
if(dabs(dx(ix)).ge.daminf) go to 5
|
|
daminf = dabs(dx(ix))
|
|
5 ix = ix + incx
|
|
10 continue
|
|
return
|
|
c
|
|
c code for increment equal to 1
|
|
c
|
|
20 daminf = dabs(dx(1))
|
|
do 30 i = 2,n
|
|
if(dabs(dx(i)).ge.daminf) go to 30
|
|
daminf = dabs(dx(i))
|
|
30 continue
|
|
return
|
|
end
|