KTH framework for Nek5000 toolboxes; testing version  0.0.1
idamax.f
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1  integer function idamax(n,dx,incx)
2 c
3 c finds the index of element having max. absolute value.
4 c jack dongarra, linpack, 3/11/78.
5 c modified 3/93 to return if incx .le. 0.
6 c modified 12/3/93, array(1) declarations changed to array(*)
7 c
8  double precision dx(*),dmax
9  integer i,incx,ix,n
10 c
11  idamax = 0
12  if( n.lt.1 .or. incx.le.0 ) return
13  idamax = 1
14  if(n.eq.1)return
15  if(incx.eq.1)go to 20
16 c
17 c code for increment not equal to 1
18 c
19  ix = 1
20  dmax = dabs(dx(1))
21  ix = ix + incx
22  do 10 i = 2,n
23  if(dabs(dx(ix)).le.dmax) go to 5
24  idamax = i
25  dmax = dabs(dx(ix))
26  5 ix = ix + incx
27  10 continue
28  return
29 c
30 c code for increment equal to 1
31 c
32  20 dmax = dabs(dx(1))
33  do 30 i = 2,n
34  if(dabs(dx(i)).le.dmax) go to 30
35  idamax = i
36  dmax = dabs(dx(i))
37  30 continue
38  return
39  end
idamax
integer function idamax(n, dx, incx)
Definition: idamax.f:2