c**************************************************************** 
c 
c subroutine bsolve appears as figure 14.17 in "introduction to 
c computing" by dyck, v.a., lawson, j.d., and smith, j.a.,
c copyright 1979 by reston publishing company.
c 
c subprogram to solve a triangular system of n equations
c in n unknowns.
c 
C SLIGHTLY MODIFIED FOR UNIX f77 COMPILER, August 15,1987
C
c*****************************************************************
c 
c n    - the actual size of all arrays
c ndim - the variable dimension of all arrays 
c t    - upper triangular coefficient matrix of size nxn
c        (assumed to be non-singular) 
c c    - right hand side of the system
c z    - solution of the system of equations
c sum  - temporary storage for sum of products
c 
c*****************************************************************
c 
      subroutine bsolve(ndim,n,t,z,c)
c
      integer ndim, n, i, j
      real t(ndim,ndim), z(ndim), c(ndim), sum
c 
c starting with z(n) = c(n)/t(n,n), 
c solve for z(n-1), z(n-2), ... , z(1). 
c 
      i = n 
C
C We believe these are WHILE loops
C If you can prove otherwise, Self Paced Cntr will give you 1 quart of Ice Cream
C 
1     if(i .ge. 1) then
         sum = c(i) 
         j = i + 1
10       if(j .le. n) then 
            sum = sum - t(i,j)*z(j) 
            j = j + 1 
         go to 10
	 endif
         z(i) = sum/t(i,i)
         i = i - 1
      go to 1
      endif 
      return
      end