Calculating Col Mean () for a subset of rows in JSL Script?

[#1]

Hi JMP Community,

What us the proper syntax in JSL for calculating the column mean (or other statistics) for a variable defined subset of rows? In a data table, I can just used the formula "Col Mean (:Data Column, :Grouping Column)" but in a JSL script this does not seem to be a correct usage.

Of note, I'm thinking of using brute force by using a "For each row" structure but that seems quite inefficient in the evaluation of 200+ columns with 1000 rows.

Thank you for your help.

TS

[#2]

Hi JMP Community,

Here is what I have come up with using the "For Each Row" structure:

Names Default to Here (1);

dt = Current Data Table ();

ALL_MEAN = Col Mean (:DATA);
MAX_MEAN = -1000;

For Each Row (
	if (MAX_MEAN < Col Mean(:DATA, :GROUP,:SGROUP), MAX_MEAN = Col Mean(:DATA, :GROUP,:SGROUP))
);

Show (ALL_MEAN);
Show (MAX_MEAN);

Any idea on making this more efficient?

Thanks,

TS

[#3 · Accepted solution]

I believe the simplest and most efficient way to do this is to use 

     Tables==>Summary

This will create a data table very fast, from which you can get your statistics for your JSL, or if you need to have the  statistics back into the original data table, a simple Update with matching will do that.  Handling 200 columns and 1000 rows is not a problem at all.  Below is a simple example that will illustrate how to do this.

names default to here(1);
dt=Open("$SAMPLE_DATA/semiconductor capability.jmp");

colNamesLIst = dt << get column names(continuous);

dtStats = dt << Summary(invisible,
	Group( :SITE ),
	Mean( colNamesList ),
	Freq( "None" ),
	Weight( "None" ),
	Link to original data table(0)
	);
	
	dt << Update( 
	With( dtStats ),
	Match Columns( :SITE = :SITE )
);

close( dtStats, nosave );