Setting Panel Axis Features

The axes for classification panels are always external to the cells and displayed as axes for the rows or columns.

Controlling Data Ranges of Rows or Columns

The strength of a classification panel presentation is that it makes it easy to visually compare similar plots across data categories. In the following example, the profits for Darts, Golf, and Baseball are compared:

proc template;
 define statgraph unionall;
  begingraph / designwidth=350px
               designheight=400px;
    entrytitle 
      "Yearly Profit for Sports Products";

    layout datapanel
        classvars=(product_group)/
        rowdatarange=unionall ;
      layout prototype;
        barchart x=year y=profit /
          stat=sum;
      endlayout;
    endlayout;
  endgraph;
 end;
run;

proc sgrender data=sashelp.orsales
              template=unionall;
  where product_group in 
       ("Golf" "Darts" "Baseball");
run;

By default, the minimum and maximum data ranges over all rows in all panels are used to establish identical data ranges across for axes that appear in the rows. The same is true for columns. The options that set these defaults are ROWDATARANGE=UNIONALL and COLUMNDATARANGE=UNIONALL. In most cases, these settings simplify quick comparisons because the axis for each row is scaled identically. Likewise, all columns share a common scale. So the graph just shown does a good job of showing that Golf products in general provide more profits than Darts or Baseball, but it does not do a very good job of showing the yearly variation in Baseball profits because those profits are so small relative to Golf profits.

To set independent axis scaling within each row, you can set ROWDATARANGE=UNION. Similarly, to set independent axis scaling within each column, you can set COLUMNDATARANGE=UNION. The following panel shows independent axes for each row. Now only the data minimum and data maximum for the cells in each row are considered in deciding the axis range.

layout datapanel classvars=(product_group)  /
                 rowdatarange=union ;

In this graph, the relative yearly trends for all product groups are equally apparent, but it is harder to judge which product group is most profitable because bar lengths are comparable only within each row.

Setting Axis Options

Classification panels use the ROWAXISOPTS=(axis-opts) and COLUMNAXISOPTS= (axis-opts) options to set axis features. Options are available for all four axis types (LINEAR, DISCRETE, LOG, and TIME), and most of the available axis options are a slightly restricted set of the axis options that are available in an OVERLAY layout.

To demonstrate the use of axis options, the following example suppresses the row axis label because the tick values are formatted with the DOLLAR format and the axis label is therefore not needed. The column axis label is suppressed because the panel's title indicates what the bars represent. Adding title information and eliminating axis labels is a good way to make more space available to the panel's grid. Axis ticks on a discrete axis (YEAR) are often not needed, so the example suppresses them. It also turns on grid lines to make comparisons easier.

You have probably noticed in the examples with bar charts that the bars do not touch the axis. This happens because a default minimum axis offset is applied to the axis to avoid possible tick value collision with an adjacent cell. This example overrides the default offset by setting OFFSETMIN=0, thus enabling the bars to touch the horizontal axis.

layout datapanel  classvars=(product_group)  /
  rowdatarange=union
  columnaxisopts=(display=(tickvalues))
  rowaxisopts=   (display=(tickvalues)
                  linearopts=(tickvalueformat=dollar12.)
                  griddisplay=on offsetmin=0) ;

Any DATAPANEL display that uses one or two classifiers can be converted to a DATALATTICE display. When the ROWVAR= option is used on the LAYOUT DATALATTICE statement, the cell headers automatically become row headers. When the COLVAR= option is used, cell headers automatically become column headers. On the following LAYOUT DATALATTICE statement, the ROWVAR= option is used, and the values of the classifier are displayed as row headers:

layout datalattice rowvar=product_group  /
  rowdatarange=union
  rowgutter=5px
  columnaxisopts=(display=(tickvalues))
  rowaxisopts   =(display=(tickvalues)
                  linearopts= (tickvalueformat=dollar12.)
                  griddisplay=on offsetmin=0);