Scripting Guide - SAS

304 Data Tables Chapter 9
Calculations
For the Big Class data set, Col Mean(Height) is 62.55 and Col Std Dev(Height) is 4.24. So for each
row, the formula above would subtract 62.55 from that row’s height value and then divide by 4.24.
Note: The pre-evaluated functions disregard the excluded row state, so any excluded rows are included in
calculations. For summary statistics that obey row exclusion, use the Distribution platform.
Columnwise Functions
The functions whose names begin with “Col” all work columnwise, or down the values in the specified
column, and return a single number. For example, Col Mean(height) finds the mean of the values in all
the rows of the column height and returns it as a scalar result. Some examples:
Rowwise Functions
Average Student Height = Col Mean(height);
Height Sigma = Col Std Dev(height);
The functions without “Col” listed below work rowwise across the values in the variables specified and
return a column result. For example, Mean(height, weight) finds the mean of the height and weight for
the current row of the data table. The rowwise statistics are valid only when used in an appropriate data
table row context. Here are some possibilities:
// scalar result for row 7 assigned to JSL global variable
row()=7; ::scalar = Mean(height, weight);
// formula column created in data table
new column("Scaled Ht-Wt Ratio",
formula(mean(height, weight)/age));
// vector of results
vector=J(1,40); // create a 1x40 matrix to hold results
for each row(vector[row()]=mean(height,weight)); //fill vector
Rowwise functions can also take vector (column matrix) or list arguments:
myMu=mean([1 2 3 4]); mySigma=stddev({1, 2, 3});
Calculator Formulas
JMP enables you to store formulas in columns that are automatically evaluated to create the values in the
cells of the column. If you open the formula, you get a calculator interface to edit the formula structurally.
However, the formula is implemented with JSL, and you can obtain the text JSL form of any expression in
the calculator by double clicking on it. The text can be edited, and when it is defocused, it is compiled back
into the structural form.
There is no difference between a formula column created through the calculator window and one created
directly through JSL with commands such as New Column(..., Formula(...)) or
Col