fix bug in gnssir_cl.py

gnssrefl/gnssir_cl.py

@@ -277,14 +277,15 @@ def gnssir(station: str, year: int, doy: int, snr: int = 66, plt: bool = False,
 
     # this is for when you want to run the code with just a single frequency, i.e. input at the console
     # rather than using the input restrictions
-    if fr is not None:
+    #print(lsp['freqs'])
+    #if fr is not None:
+    if len(fr) > 0:
         lsp['freqs'] = fr
         # better make sure you have enough amplitudes
         ampl_from_json = lsp['reqAmp'][0]
         if ampl is None:
             lsp['reqAmp'] = [ampl_from_json for i in range(14)]
 
-
     if ampl is not None:
         # this is not elegant - but allows people to set ampl on the command line
         # but use the frequency list from their json ...  which i think has max of 12