## vbars prefab | Welcome Gallery Handbook |
| Manual page for vbars_prefab(PL)

## EXAMPLE 1

      pl  -prefab vbars  data=data4  delim=tab  x=1  y=2  vals=yes\
           yrange=0  yinc=20  ygrid=yes  barwidth=0.3

    	data4 file:
    		Group A	78	7
    		Group B	84	12
    		Group C	56	6

## EXAMPLE 2

       pl -prefab vbars  data=data5  delim=tab  x=1  y=2  err=3  \
       y2=4  err2=5  errunder=yes  ygrid=yes  barwidth=0.1  \
         name=Treatment  name2=Control stubvert=yes

        data5 file:
    	Test 3	76	19	84	14
    	Test 4	83	12	64	9
    	Test 5	95	11	92	13
    	...etc..

## EXAMPLE 3

      pl -prefab vbars  data=data5  delim=tab  x=1  y=2  err=3  y2=4  \
      err2=5   erronly=yes   name=Treatment  name2=Control  stubvert=yes \
      errcolor=red  errcolor2=blue  sep=0.08  xgrid=yes  ylog=log

## EXAMPLE 4

       pl -prefab vbars  data=data18  x=1  y=2  crossover=0  \
       color=blue  vals=yes

       The data18 file:
    	1992	-47
    	1993	-63
    	1994	-24
    	1995	12
    	..etc.

How to run these examples

## DESCRIPTION

`vbars` is a prefab for producing bar graphs with vertical solid bars for one or two groups.`` Two groups of values may be displayed if y2 (etc) are used, as in the second example.`` Error bars may be added above or below the bar graph, or error bars alone may be rendered.`` By default the X axis is categories, but it may be continuous numeric if xnumeric is used (for chronological data use the chron prefab ).`` This prefab is based on proc bars .``

## PARAMETERS

  standard prefab parameters are all supported. data, x and y are required.`` y values should be numeric and will determine the height of bars.`` x values determine bar locations.``

  color is the color of the first set of filled bars (default = orange)

  barwidth is the width of the filled bars. This is a value in inches, or may be given as `line` for very thin bars.``

  errcolor is the error bar color for the error bars associated with the first set of bars (default = black).``

  errwidth is the width of error bar tails in inches (default = 0.08)

  errthick is the thickness of the error bar lines (default = 0.5)

  errunder may be set to `yes` if error bars should be drawn "under" the filled bars (only the upward error bar is thus visible).``

  erronly may be set to `yes` if error bars only are desired, without any filled bars.``

  xnumeric may be specified as `yes` to signify that X values are numeric and not categories.``

  vals may be specified as `yes` to indicate that the numeric values should be displayed near the top of each bar.``

  crossover may be specified as the value in Y where bars begin to point downward instead of upward. For instance, `crossover=0` is often useful when dealing with financial income, to show loss using downward bars.``

  curve may be given as `yes`, or as a linedetails attribute, which causes a moving average curve to be fit to bars, and drawn behind the bars. Not applicable to a second set of bars.`` The order parameter may be set to the number of preceding data points to be considered when computing averages (default = 5).``

The following parameters are used when displaying two groups of values.`` The second example above illustrates.``

  y2, color2, err2, and errcolor2 control the size and color of the second set of bars, and the magnitude and color of error bars associated with the second set. Default color2 is green.``

  sep controls bar separation (default=0.15)

  name and name2 should be given as legend labels for the two groups

  legend controls the location of the legend. Example: `"legend=1 0.5"` Default is `min+0.4 max`.``
  data display engine
  Copyright Steve Grubb

Markup created by unroff 1.0, `` `` September 14, 2001.