Frequency

The frequency option makes the data monotonic in x; points with the same x-value are replaced by a single point having the summed y-values. To plot a histogram of the number of data values in equal size bins, set the y-value to 1.0 so that the sum is a count of occurances in that bin: Example:

    binwidth = <something>  # set width of x values in each bin
    bin(val) = binwidth * floor(val/binwidth)
    plot "datafile" using (bin(column(1))):(1.0) smooth frequency