Fixed sort of zero-length array in wsjt1.

git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/trunk@39 ab8295b8-cf94-4d9e-aec4-7959e3be5d79

ssort.f

@@ -26,8 +26,7 @@ c            = -2  means sort x in decreasing order and carry y along.
 
       nn = n
       if (nn .lt. 1) then
-         print *,
-     +      'the number of values to be sorted is not positive.'
+         print *,'n = ',nn,'   kflag = ',kflag,' in ssort.'
          return
       endif
 c

wsjt1.f

@@ -264,9 +264,10 @@ C  Now the multi-tone decoding
      +    cfile6,ps0)
 
 	npkept=nline             !Number of pings that were kept
-	call indexx(npkept,tping,indx)  !Merge the ST and MT decodes
 	smax=0.
 	stbest=.false.
+	if(npkept.gt.0) then
+	   call indexx(npkept,tping,indx) !Merge the ST and MT decodes
 	   do i=1,npkept
 	      j=indx(i)
 	      if(pick .and. STFound .and.
@@ -282,6 +283,7 @@ C  Now the multi-tone decoding
 		 stbest = (msg3.ne.'   ')
 	      endif
  10	   enddo
+	endif
 
 	dt=1.0/11025.0                !Compute spectrum for pink curve
 	if(stbest) then