maxmin.src

#include "zeus2d.def"
c=======================================================================
c//////////////////////////  SUBROUTINE MAXMIN  \\\\\\\\\\\\\\\\\\\\\\\\
c
      subroutine maxmin(qin,q1,q2,ii,io,js,je,qmin,qmax)
c
c  PURPOSE: This subroutine returns the minimum and maximum of the
c  2-D zone centered array qin over all active grid zones.  Uneven
c  boundaries, eg steps and jumps, can be accounted for.
c
c  INPUT ARGUMENTS:
c    qin   = the 2-D array to be searched
c    q1,q2 = 1-D worker arrays with dimensions of the trailin index of q
c    ii,io = vectors of starting and ending indices in the 1-direction
c            (permits using uneven boundaries, eg steps and jumps)
c    js,je = scalars of smallest starting index and largest ending index
c            in 2-direction
c
c  OUTPUT ARGUMENTS:
c    qmin = minimum value
c    qmax = maximum value
c
c  LOCALS:
c----------------------------------------------------------------------
      implicit NONE
#include "param.h"
      REAL     qin(in,jn),q1(jn),q2(jn),qmin,qmax
      integer  ii(jn),io(jn),js,je
c
      integer  i,j
c\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\///////////////////////////////////
c=======================================================================
c
      do 20 j=js,je
        q1(j)= qin(ii(j),j)
        q2(j)= qin(ii(j),j)
	do 10 i=ii(j),io(j)
	  q1(j) = max(q1(j), qin(i,j))
	  q2(j) = min(q2(j), qin(i,j))
10      continue
20    continue
c
      qmax = q1(js)
      qmin = q2(js)
      do 30 j=js,je
	qmax = max(qmax, q1(j))
	qmin = min(qmin, q2(j))
30    continue
c
      return
      end