WSJT-X/lib/fchisq0.f90
Joe Taylor 15ddaf9e8a Various changes to JT65 decoding, all potentially temporary.
1. Measure Doppler width by fitting a (modified) Lorentzian.
2. Don't call "slope" in sync65().
3. New definition of "sync1".
4. Get snr from sync1.


git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/wsjtx@6536 ab8295b8-cf94-4d9e-aec4-7959e3be5d79
2016-03-17 18:52:06 +00:00

24 lines
405 B
Fortran

real function fchisq0(y,npts,a)
real y(npts),a(4)
rewind 51
chisq = 0.
do i=1,npts
x=i
z=(x-a(3))/(0.5*a(4))
yfit=a(1)
if(abs(z).lt.3.0) then
d=1.0 + z*z
yfit=a(1) + a(2) * (1.0/d - 0.1)
endif
chisq=chisq + (y(i) - yfit)**2
! write(51,3001) i,y(i),yfit,y(i)-yfit
!3001 format(i5,3f10.4)
enddo
fchisq0=chisq
return
end function fchisq0