#!/bin/sh
#
# produce a simple ascii scaled bar-plot of input values.
#
# Usage: barplot [-nc #] [-lc #] [-lw #] [-pw #] [-is] [files]
# 	-nc/-lc set number/label column, respectively
# 	-lw/-pw set label/plot width, respectively
#	-sn	set value to subtract from each value to be plotted
#	-is	set initial maximum value (to force plotting to a known scale)
#
# Corey Satten, corey @ cac.washington.edu, 2/12/92
# http://staff.washington.edu/corey

LABWIDTH=8			# width of value field at left
PLOTWIDTH=79			# width of entire plot
LCOL=1				# default label column
NCOL=1				# default number column
SN=0				# default number to subtract
MAX=0				# forced maximum

for i in $*; do
    case "$1" in
	-lc)	LCOL=$2; FLD=$2; shift; shift;;		# label from column #
        -nc)	NCOL=$2; FLD=$2; shift; shift;;		# number from column #
        -is)	MAX=$2; FLD=$2; shift; shift;;		# initial maximum
        -lw)	LABWIDTH=$2; shift; shift;;		# value field width
        -pw)	PLOTWIDTH=$2; shift; shift;;		# scale plot to width
        -sn)	SN=$2; shift; shift;;			# subtract from each #
	-*)	echo unknown flag 1>&2; exit 1;;
	*)	break;;		# end option parsing
    esac
done

awk "
BEGIN	{ max = $MAX }
	{
	num = \$($NCOL) - $SN		# subtract SN from all input nums
	if (num < min) min = num 	# compute minimum input number if < 0
	if (num > max) max = num	# compute maximum input number
	val[NR] = num			# save input number value
	lab[NR] = \$($LCOL)		# save input label value
	}
END	{
	dashes = \"------------------------------------------------------\"
	while (length(dashes) < $PLOTWIDTH) dashes = dashes dashes
	scale = ($PLOTWIDTH-$LABWIDTH-1)/(max-min)
	for (i=1; i <= NR; ++i) {
	    len = int((val[i]-min)*scale+.5);
	    printf (\"%-$LABWIDTH.${LABWIDTH}s%s|\\n\", \
		lab[i], substr(dashes,1,len))
	    }
	}
" $*