WSJT-X/lib/unpackbits.f90
Joe Taylor a67d17316f Rename library directory
git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/wsjtx@2635 ab8295b8-cf94-4d9e-aec4-7959e3be5d79
2012-10-03 14:31:43 +00:00

25 lines
517 B
Fortran

subroutine unpackbits(sym,nsymd,m0,dbits)
! Unpack bits from sym() into dbits(), one bit per byte.
! NB: nsymd is the number of input words, and m0 their length.
! there will be m0*nsymd output bytes, each 0 or 1.
integer sym(nsymd)
integer*1 dbits(*)
integer*1 n1
equivalence (n,n1)
k=0
do i=1,nsymd
mask=ishft(1,m0-1)
do j=1,m0
k=k+1
dbits(k)=0
if(iand(mask,sym(i)).ne.0) dbits(k)=1
mask=ishft(mask,-1)
enddo
enddo
return
end subroutine unpackbits