1!
2!     CalculiX - A 3-dimensional finite element program
3!     Copyright (C) 1998-2021 Guido Dhondt
4!
5!     This program is free software; you can redistribute it and/or
6!     modify it under the terms of the GNU General Public License as
7!     published by the Free Software Foundation(version 2);
8!
9!
10!     This program is distributed in the hope that it will be useful,
11!     but WITHOUT ANY WARRANTY; without even the implied warranty of
12!     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13!     GNU General Public License for more details.
14!
15!     You should have received a copy of the GNU General Public License
16!     along with this program; if not, write to the Free Software
17!     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
18!
19      subroutine subtracthmatrix(neqp,aubh,adbh,aux,dp,jqp,irowp,b,
20     &     theta1,dtimef)
21!
22!     transfer effect of H-matrix for compressible fluids to the
23!     rhs
24!
25      implicit none
26!
27      integer i,j,neqp,ir,ic,jqp(*),irowp(*)
28!
29      real*8 aux(*),aubh(*),adbh(*),dp(*),value,constant,theta1,dtimef,
30     &     b(*)
31!
32      do i=1,neqp
33        aux(i)=adbh(i)*dp(i)
34      enddo
35!
36      do ic=1,neqp
37        do j=jqp(ic),jqp(ic+1)-1
38          ir=irowp(j)
39          value=aubh(j)
40          aux(ir)=aux(ir)+value*dp(ic)
41          aux(ic)=aux(ic)+value*dp(ir)
42        enddo
43      enddo
44!
45      constant=dtimef*dtimef*theta1
46!
47      do i=1,neqp
48        b(i)=b(i)-constant*aux(i)
49      enddo
50!
51      return
52      end
53
54