topic Re: Associative Array as Table Variable in Discussions

Associative Array as Table Variable

robot — Fri, 15 Aug 2025 00:14:06 GMT

Is it possible to create an Associative Array as a Table Variable and then use stored values in a column formula?

I have a number of related variables I would like to edit as part of an ongoing analysis. These variables will then be used like a Match function in a column formula.

For example:

Create table variable counts and set value to ["a" => 10, "b" => 3, "c" => 1].
counts is then referenced by a column formula, like :counts[:col]. Where :col is a Character column with values "a", "b", or "c".

Is this possible? I am using JMP 18.2.1.

Re: Associative Array as Table Variable

Craige_Hales — Fri, 15 Aug 2025 02:06:32 GMT

I think this does what you asked:

New Table( "Untitled",
	Add Rows( 3 ),
	New Table Variable( "abc", "[\!"a\!"=>1, \!"b\!"=>2, \!"c\!"=>4]" ),
	New Column( "Column 1",
		Numeric,
		"Nominal",
		Format( "Best", 9 ),
		Formula(
			c_abc = As Constant( Eval( Parse( :abc ) ) );
			c_abc["c"];
		),
		Set Selected
	)
)

Note the table variable is just text, so it gets parsed and evaluated. The AsConstant function makes it only parse/eval once for the entire column's evaluation, so it won't be too inefficient.

As an alternative, you could have a separate table variable for each element of the associative array. It might be easier to edit, but it won't create an isolated namespace like the associative array.

Another alternative is to use custom column properties if the names are going to be column names. They might be harder to find and edit. Unlike the text-only table variable, they also hold expressions:

dt=New Table( "Untitled",
	New Column( "Column 1",
		Set Property( "xxxxx", ["a"=>42,"adfasdfasdf"=>77] )
	)
);

(dt:column1<<getproperty("xxxxx"))["a"] // 42

Re: Associative Array as Table Variable

jthi — Fri, 15 Aug 2025 05:49:50 GMT

Craige did provide a good options how you can do this. Here is a wish list item hoping for more complicated data types for table variables

Re: Associative Array as Table Variable

robot — Fri, 15 Aug 2025 16:24:38 GMT

Thanks @Craige_Hales , your solution works great.

Thanks @jthi , I upvoted this suggestion.