qinit.f.html CLAWPACK  
 Source file:   qinit.f
 Directory:   /Users/rjl/clawpack_src/clawpack_master/amrclaw/examples/burgers_2d_square
 Converted:   Mon Feb 19 2024 at 17:57:30   using clawcode2html
 This documentation file will not reflect any later changes in the source file. 

 

c
c
c
c     =====================================================
       subroutine qinit(meqn,mbc,mx,my,xlower,ylower,
     &                   dx,dy,q,maux,aux)
c     =====================================================
c
c     # Set initial conditions for q.
c     # Sample scalar equation with data that is piecewise constant with
c     # q = 1.0  if  0.1 < x < 0.6   and   0.1 < y < 0.6
c     #     0.1  otherwise
c
       implicit double precision (a-h,o-z)
       dimension q(meqn, 1-mbc:mx+mbc, 1-mbc:my+mbc)
       dimension aux(maux, 1-mbc:mx+mbc, 1-mbc:my+mbc)
c
       do 20 i=1,mx
          xi = xlower + (i-0.5d0)*dx
          do 20 j=1,my
             yj = ylower + (j-0.5d0)*dy
             if (xi.gt.0.1d0 .and. xi.lt.0.6d0 .and.
     &           yj.gt.0.1d0 .and. yj.lt.0.6d0) then
                     q(1,i,j) = 1.d0
                   else
                     q(1,i,j) = 0.1d0
                   endif
  20         continue
       return
       end