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A *range* is a list of two numbers, the minimum and the maximum.
Ranges can be given explicity or computed in PostScript by
`column-range`

.

- Function:
**column-range***array k* -
Returns the range of values in 2-dimensional

`array`column`k`.

- Function:
**pad-range***range p* -
Expands

`range`by`p`/100 on each end.

- Function:
**snap-range***range* -
Expands

`range`to round number of ticks.

- Function:
**combine-ranges***range1 range2 …* -
Returns the minimal range covering all

`range1`,`range2`, ...

- Function:
**setup-plot***x-range y-range pagerect* - Function:
**setup-plot***x-range y-range* `x-range`and`y-range`should each be a list of two numbers or the value returned by`pad-range`

,`snap-range`

, or`combine-range`

.`pagerect`is the rectangle bounding the graph to be drawn; if missing, the rectangle from the top of the PostScript stack is popped and used.Based on the given ranges,

`setup-plot`

sets up scaling and margins for making a graph. The margins are sized proportional to the`fontheight`value at the time of the call to setup-plot.`setup-plot`

sets two variables:`plotrect`The region where data points will be plotted.

`graphrect`The

`pagerect`argument to`setup-plot`

. Includes plotrect, legends, etc.