Files
piscal/dataassim/math/numrec/f77_sources/mpinv.for
T
2016-02-03 18:52:05 +00:00

35 lines
871 B
Fortran

SUBROUTINE mpinv(u,v,n,m)
INTEGER m,n,MF,NMAX
CHARACTER*1 u(n),v(m)
REAL BI
PARAMETER (MF=4,BI=1./256.,NMAX=8192)
CU USES mpmov,mpmul,mpneg
INTEGER i,j,mm
REAL fu,fv
CHARACTER*1 rr(2*NMAX+1),s(NMAX)
if(max(n,m).gt.NMAX)pause 'NMAX too small in mpinv'
mm=min(MF,m)
fv=ichar(v(mm))
do 11 j=mm-1,1,-1
fv=fv*BI+ichar(v(j))
11 continue
fu=1./fv
do 12 j=1,n
i=int(fu)
u(j)=char(i)
fu=256.*(fu-i)
12 continue
1 continue
call mpmul(rr,u,v,n,m)
call mpmov(s,rr(2),n)
call mpneg(s,n)
s(1)=char(ichar(s(1))-254)
call mpmul(rr,s,u,n,n)
call mpmov(u,rr(2),n)
do 13 j=2,n-1
if(ichar(s(j)).ne.0)goto 1
13 continue
continue
return
END