qinit.f.html | |
Source file: qinit.f | |
Directory: /Users/rjl/clawpack_src/clawpack_master/apps/fvmbook/chap20/burgers | |
Converted: Sat Mar 23 2024 at 11:04:47 using clawcode2html | |
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c c c c ===================================================== subroutine qinit(meqn,mbc,mx,my,xlower,ylower, & dx,dy,q) c ===================================================== c c # Set initial conditions for q. c # A square region where q=1 together with a cone c implicit double precision (a-h,o-z) dimension q(meqn,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.lt.0.6d0 .and. xi.gt.0.1d0 .and. yj.gt.-0.25d0 .and. & yj.lt.0.25d0) then q(1,i,j) = 1.d0 else q(1,i,j) = 0.d0 endif r = dsqrt((xi+0.45d0)**2 + yj**2) if (r .lt. 0.35d0) then q(1,i,j) = 1.d0 - r/0.35d0 endif 20 continue return end