RFI histograms

Click graphs to enlarge.
April 5 2016
multibeam: time and freq scales = 1
zone RFI removed before multibeam check
April 6 2016
multiband: freq scale 5, time scale 3
April 8 2016
graph scores rather than power
check independently for zone and MB
5/3 scale factors
April 14

Add low-chirp-rate RFI removal
fullsky.  May 15 2016
first try with new zone finder.
1% of bins are marked as zones.
RFI zones are 2% of bins
Sept 22 2016
Time scale for multibeam rectangles changed from 3 to 11.
Freq scale is 5.
Zone RFI fraction is .05 for spike, .02 for others
RFI bins are now an integer multiple of FFT bins.
Include signals at extremes of detection freq.