## proc legendentry

Version 2.32
Scripts

Manual page for proc_legendentry(PL)

Explicitly defines one legend entry.`` This entry will be rendered the next time that proc legend is executed.`` Usually, legends are built by successive plotting procs having a `legendlabel` attribute. However, if additional flexibility is needed to make custom legend entries, this proc may be invoked, once per legend entry.``

For example, if a scatterplot is being created with various sized points, there is no automatic way to get a legend of the various point sizes, so proc legendentry could be executed (probably several times) to define legend information, then proc legend could be executed to render it.``

proc legendentry is also useful in setting up legend-driven plots which allow things like bar color, or scatterplot symbol color, size, or shape to be controlled by a data field.``

A gallery example that uses this proc is scatterplot3a.``

## Attributes

sampletype t

  The type of sample to be displayed with the entry.`` t may be one of: `line`, `color`, `symbol`, `text`, `line+symbol`, or `text+symbol`.`` It may also be `none`, in order to insert spacing into the legend.``
  Example: `sampletype: text`

label text

  The label for the legend entry.`` The `\n` construct can be used to force a line break when the legend is displayed, or the label can be wordwrapped using proc legend wraplen attribute.``
  Example 1: `label: Eastern counties`
  Example 2: `label: Response curve \n for 30 mg dose`

tag string

  An optional short identifier to be associated with the entry, so that the entry can be accessed later.`` Used with proc bars colorfield, as in this example: colorfld

details spec
details2 spec
details3 spec

  Details regarding the rendering of the sample. Exactly what should be supplied for `details`, `details2` and perhaps `details3` depends on the `sampletype`:

      sampletype            details           details2        details3
      ----------          ------------      -------------   -----------
      line                linedetails       -               -
      color               color             -               -
      symbol              symboldetails     -               -
      text                a char or word    textdetails     -
      line+symbol         linedetails       symboldetails   -
      text+symbol         a char or word    textdetails     symboldetails

  Explanations of types: color linedetails symboldetails textdetails

## Legend-driven technique

This is a technique where the legend table mechanism serves to map certain data values to ploticus colors or other appearance attributes.`` For example, suppose field 3 of your data is a group code of either A, B, or C.`` You could use legend-driven technique to render 'A' data rows in red, 'B' in blue, and 'C' in green.``

Here's how you do it:

  1. For every expected variation, set up an explicit legend entry using proc legendentry.`` `label`, `tag`, and `details` attributes should be supplied.`` The `tag` will be compared with data field contents.`` The `details` attributes control appearance.``
  2. Plot, using the appropriate attribute. For example, if you are doing a bar graph where individual bar colors are controlled by a data field, you would use proc bars and specify a `colorfield`.``

Examples of legend-driven technique are colorfld symfld symfld dupsleg
data display engine
Copyright Steve Grubb

Markup created by unroff 1.0, `` `` August 23, 2005.