Histograms do not show when the cache is filled with zeroes

[smaeul]

I ran into this by running the program on sorted data that began with over 1000 lines of "0".

$ yes 0 | head -n 1000 > file
$ echo 1 >> file
$ clistats.exe -hg 10 < file
No valid data

$ clistats.exe -hg 10,1001 < file
#==================================================================
#                    Histogram of 1
#==================================================================
#       Bin        Min        Max   Frequency        PDF        CDF
          0   0.000000   0.100000        1000   0.999001   0.999001
          1   0.100000   0.200000           0   0.000000   0.999001
          2   0.200000   0.300000           0   0.000000   0.999001
          3   0.300000   0.400000           0   0.000000   0.999001
          4   0.400000   0.500000           0   0.000000   0.999001
          5   0.500000   0.600000           0   0.000000   0.999001
          6   0.600000   0.700000           0   0.000000   0.999001
          7   0.700000   0.800000           0   0.000000   0.999001
          8   0.800000   0.900000           0   0.000000   0.999001
          9   0.900000   1.000000           1   0.000999   1.000000