Try to avoid a crash in freqcal.f90 when data is all zeros.

This commit is contained in:
Steven Franke 2019-05-11 09:36:15 -05:00
parent c393740b0a
commit ab1454a24c

View File

@ -41,6 +41,7 @@ subroutine freqcal(id2,k,nkhz,noffset,ntol,line)
endif
smax=0.
s=0.
ipk=-99
do i=ia,ib
s(i)=real(cx(i))**2 + aimag(cx(i))**2
if(s(i).gt.smax) then
@ -48,25 +49,32 @@ subroutine freqcal(id2,k,nkhz,noffset,ntol,line)
ipk=i
endif
enddo
call peakup(s(ipk-1),s(ipk),s(ipk+1),dx)
fpeak=df * (ipk+dx)
ap=(fpeak/fs+1.0/(2.0*NFFT))
an=(fpeak/fs-1.0/(2.0*NFFT))
sp=sum(id2((k-NFFT):k-1)*cmplx(cos(xi*ap),-sin(xi*ap)))
sn=sum(id2((k-NFFT):k-1)*cmplx(cos(xi*an),-sin(xi*an)))
fpeak=fpeak+fs*(abs(sp)-abs(sn))/(abs(sp)+abs(sn))/(2*NFFT)
xsum=0.
nsum=0
do i=ia,ib
if(abs(i-ipk).gt.10) then
xsum=xsum+s(i)
nsum=nsum+1
endif
enddo
ave=xsum/nsum
snr=db(smax/ave)
pave=db(ave) + 8.0
if(ipk.ge.1) then
call peakup(s(ipk-1),s(ipk),s(ipk+1),dx)
fpeak=df * (ipk+dx)
ap=(fpeak/fs+1.0/(2.0*NFFT))
an=(fpeak/fs-1.0/(2.0*NFFT))
sp=sum(id2((k-NFFT):k-1)*cmplx(cos(xi*ap),-sin(xi*ap)))
sn=sum(id2((k-NFFT):k-1)*cmplx(cos(xi*an),-sin(xi*an)))
fpeak=fpeak+fs*(abs(sp)-abs(sn))/(abs(sp)+abs(sn))/(2*NFFT)
xsum=0.
nsum=0
do i=ia,ib
if(abs(i-ipk).gt.10) then
xsum=xsum+s(i)
nsum=nsum+1
endif
enddo
ave=xsum/nsum
snr=db(smax/ave)
pave=db(ave) + 8.0
else
snr=-99.9
pave=-99.9
fpeak=-99.9
ferr=-99.9
endif
cflag=' '
if(snr.lt.20.0) cflag='*'
n=n+1
@ -77,7 +85,7 @@ subroutine freqcal(id2,k,nkhz,noffset,ntol,line)
ncal=1
ferr=fpeak-noffset
write(line,1100) nhr,nmin,nsec,nkhz,ncal,noffset,fpeak,ferr,pave, &
snr,cflag,char(0)
snr,cflag,char(0)
1100 format(i2.2,':',i2.2,':',i2.2,i7,i3,i6,2f10.3,2f7.1,2x,a1,a1)
900 return