WSJT-X/lpf1.f
Joe Taylor 2c17544f3f initial import
git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/WSJT/trunk@1 ab8295b8-cf94-4d9e-aec4-7959e3be5d79
2005-12-22 16:40:53 +00:00

20 lines
454 B
Fortran

subroutine lpf1(data,n,nz)
C Half-band lowpass filter and decimate by 2.
real data(n)
nz=n/2 -10
do i=1,nz
j=2*i+8
data(i)=0.047579*(data(j-9)+data(j+9))
+ - 0.073227*(data(j-7)+data(j+7))
+ + 0.113449*(data(j-5)+data(j+5))
+ - 0.204613*(data(j-3)+data(j+3))
+ + 0.633339*(data(j-1)+data(j+1))
+ + data(j)
enddo
return
end