NAME

       histo - compute 1-dimensional histogram of N data columns

SYNOPSIS

       histo [-c][-p] xmin xmax nbins
       histo [-c][-p] imin imax

DESCRIPTION

       Histo  bins  columnular  data  on the standard input between the given minimum and maximum
       values.  If three command line arguments are given, the third is taken as  the  number  of
       data  bins  between the first two real numbers.  If only two arguments are given, they are
       both assumed to be integers, and the number of data bins will be equal to their difference
       plus one.  The bins are always of equal size.

       The  output  is  N+1  columns of data (for N columns input), where the first column is the
       centroid of each division, and each row corresponds to the  frequencies  for  each  column
       around that value.

       If  the -c option is present, then histo computes the cumulative histogram for each column
       instead of the straight frequencies.  The upper value of each bin is printed also  instead
       of  the centroid.  This may be useful in computing percentiles, for example.  Values below
       the minimum specified are still counted in the cumulative total.

       The -p option tells histo to report the percentage of the  total  number  of  input  lines
       rather  than  the  absolute  counts.   In  the case of a cumulative total, this yields the
       percentile values directly.  Values above the maximum are counted as well as values  below
       in this case.

       All  input  data is interpreted as real values, and columns must be white-space separated.
       If any value is less than the minimum or greater than the  maximum,  it  will  be  ignored
       unless the -c option is specified.

EXAMPLE

       To count data values between -1 and 1 in 50 bins:

         histo -1 1 50 < input.dat

       To count frequencies of integers between 0 and 255:

         histo 0 255 < input.dat

AUTHOR

       Greg Ward

SEE ALSO

       cnt(1), neaten(1), rcalc(1), rlam(1), tabfunc(1), total(1)