NAME

       braillegraph - a simple histogram tool that produces text output

SYNOPSIS

       braillegraph <data series

       psql -At -c 'select ...' |braillegraph

DESCRIPTION

       braillegraph takes a single data series and plots them abusing the Braille range
       (U+2800..U+28FF).  It is able to display two values per a horizontal character, thus a
       plain text mail can hold an X range up to ~150 data points.  The vertical resolution is
       4/character, thus a reasonable Y range is up to 80ish.

       By default, no scaling is done at all — one dot is exactly one data point horizontally, a
       value of 1 vertically.

       Input is given as one non-negative integer per line.

EXAMPLE

        psql bugs -A -t -c "
        select
            count(case when arch='amd64 (x86_64)' then 1 else null end)
            *80/count(*)
        from (select arch, date_trunc('month', timestamp) as month from si) m
        group by month
        order by month
        "|braillegraph

OPTIONS

       -h, --horizontal
           Horizontal layout.  The Y axis is left-to-right, X axis is top-to-bottom.

       -m, --max number
           Force the target range of the data.  Normally, the histogram will be auto-sized based
           on the largest value in the input; this option sets the max to a fixed value.  It will
           result either in empty space on the graph or in values over the limit being hard-
           capped.

           You typically want this option when comparing multiple histograms, or when
           continuously updating the display.

       -y, --y-scale number
           Scale the data so that the graph takes a given size (measured in dots) instead of
           varying on the data given.  The size in characters is ¼ the dot size on a vertical
           graph, ½ on horizontal.

CAVEATS

       Versions of FreeFont older than end of 2016 make any Braille glyphs (both for legitimate
       uses and for brailleimg) totally unreadable at pixel sizes commonly found in computer
       displays — ie, anything but HiDPI and/or very large text sizes.  Alas, this font is
       commonly configured as primary fallback in default setups shipped by distributions.

AUTHOR

       Adam Borowski <kilobyte@angband.pl>

                                            2021-08-22                            BRAILLEGRAPH(1)