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)