If you're looping through a column in a file why not just use the Tabulate or Summary commands? If you are grouping things by another column you can use that as a "by" variable. For example:
| ID |
Value |
| A |
1 |
| A |
2 |
| A |
2 |
| B |
2 |
| B |
3 |
| B |
3 |
| B |
4 |
| B |
4 |
Using tabulate drag the ID and Value columns over the drop zone for rows. You'll need to change the role of Value to be a grouping variable. This is the result:
| ID |
Value |
N |
| A |
1 |
1 |
| A |
2 |
2 |
| B |
2 |
1 |
| B |
3 |
2 |
| B |
4 |
2 |
So for A you have two distinct values (1, 2), along with the number of occurrences (1, 2). For B you have three distinct values (2, 3, 4), along with occurrences (1, 2, 2).
Here's the equivalent JSL:
dt = New Table( "Test", Add Rows( 8 ),
New Column( "ID", Character, "Nominal",
Set Values( {"A", "A", "A", "B", "B", "B", "B", "B"} ) ),
New Column( "Value", Numeric, "Continuous", Format( "Best", 12 ),
Set Values( [1, 2, 2, 2, 3, 3, 4, 4] ) )
);
dtab = dt << Tabulate(
Show Control Panel( 0 ),
Add Table( Row Table( Grouping Columns( :ID, :Value ) ) ),
invisible
);
dt2 = dtab << Make Into Data Table;
