XCHART Statement: SHEWHART Procedure

Axis Labels

You can specify axis labels by assigning labels to particular variables in the input data set, as summarized in the following table:

Axis	Input Data Set	Variable
Horizontal	all	subgroup-variable
Vertical	DATA=	process
Vertical	HISTORY=	subgroup mean variable
Vertical	TABLE=	`_SUBX_`

If you specify the TRENDVAR= option, you can provide distinct labels for the vertical axes of the $\bar{X}$ and trend charts by breaking the vertical axis into two parts with a split character. Specify the split character with the SPLIT= option. The first part labels the vertical axis of the $\bar{X}$ chart, and the second part labels the vertical axis of the trend chart.

For example, the following sets of statements specify the label Residual Mean for the vertical axis of the $\bar{X}$ chart and the label Fitted Mean for the vertical axis of the trend chart:

proc shewhart data=Toolwear;
   xchart Diameter*Hour / split    = '/'
                          trendvar = Fitted ;
   label Diameter = 'Residual Mean/Fitted Mean';
run;

proc shewhart history=Regdata;
   xchart Diameter*Hour / split    = '/'
                          trendvar = Fitted;
   label DiameterX = 'Residual Mean/Fitted Mean';
run;

In this example, the label assignments are in effect only for the duration of the procedure step, and they temporarily override any permanent labels associated with the variables.