Creating formulas in a new column. JMP script

Question

Hello all. I am needing to create a new column that will subtract the contents of consecutive rows and insert that value into the new column.

Essentially I want to say: In column X, subtract row 1 from row 2 and place that value in column Y. I want this to continue for the entirety of Column X.

Therefore: Column Y = X(i+1) - Xi; i being the row number. Anyone know how to do this? Seems simple enough but I am very new to scripting and having a hard time getting something to stick.

markschahl · Answer

One addition to what Brady^2 said: you can create formula columns in any platform using this method:
https://www.jmp.com/support/help/en/16.0/#page/jmp/transform-columns-in-a-jmp-platform.shtml

I used to create a lot of formula columns in data tables. I now do less of that, and use the method above a lot.

brady_brady · Answer

Hi,

As Jim mentions, studying up will help, although admittedly the sheer volume of information can be a bit intimidating at first.

Since much of what can be accomplished through scripting can also be done interactively, be sure to check out 1-click formulas, which easily create some of the most commonly encountered formulas.

In your example, you can right-click on any value in the original column and select New Formula Column > Row > Difference from the ensuing menu. This creates a new column with the desired formula, in a single step.

Cheers,

Brady

txnelson · Answer

* You need to read the Discovering JMP document, and the Scripting Guide!
* You need to attempt to solve the problem first.  One learns by making mistakes and figuring out what the problem is
* When you fail at solving the problem, the Discussion Community is there to help.
* Below is a script that if you have setup your data table correctly, should show you one way to solve the problemNames Default to Here( 1 );

// Open Data Table: big class.jmp
// → Data Table( "big class" )
Open( "$SAMPLE_DATA/big class.jmp" );

// New column: Column 6
Data Table( "big class" ) << New Column( "New Column",
	Numeric,
	"Continuous",
	Format( "Best", 12 ),
	Formula( :weight[Row() + 1] - :weight )
);