How Do I create a Column formula for N Categories?

[#1]

I would like to create a column formula that provides a count of the number of distinct values in a column.  I can use the Column viewer, Show summary function in JMP 15 but I want to have that value in a column for use in other calculations.

For example in the Big Class Table - N Items in column "Sex" should show 2 as 2 distinct values.

[#2]

here is a wish to add such a functionality
... to JSL
... to New Column Formula
... to Graph Builder

Col N Categories 

I guess there are only a few JMP users in the world who don't need it ; )
Most JMP users will be excited to see such a functionality in a future version of JMP (... along with dense ranking )

[#3]

A little late to the thread, but I was looking for a solution to the same problem.  The formula below in @CTrahon0526 's datatable reproduces the values in "Unique Tool IDs Per Work Week Per Year" column

Col Sum( Col Cumulative Sum( 1, :Year, :WW, :Tool ID ) == 1, :Year, :WW )

[#4]

Nice, I can use this a lot - so, now I have:

Names Default To Here( 1 );
Try(dt = CurrentDataTable(), stop());


updateLBox = Function( {t},
	(t << sib) << setitems( (t << topparent)[listboxbox( 1 )] << getselected )
);

nw = New Window("count unique entries",
<< Type("Modal Dialog"),
	Border Box( Left( 10 ), Right( 10 ), bottom( 5 ),
		V List Box(
			Lineup Box( N Col( 1 ), spacing( 10 ),
				// Text Box( "XG Boost Specification" ), 
				// colistbox only necessary if the script is standalone
				H List Box(
					Panel Box( "Select Columns", Col List Box( all, nlines( 15 ) ) ),
					Panel Box( "Cast Selected Columns into Roles",
						Lineup Box( N Col( 2 ),
							Button Box("Unique",
								<<setfunction( Function( {t}, updateLBox( t ) ) )
							),
							Cunique = Col List Box( nlines( 2 ), minitems( 1 ) ),
							Button Box("By Group",
								<<setfunction( Function( {t}, updateLBox( t ) ) )
							),
							CBy = Col List Box( nlines( 2 ), minitems( 0 ) )
						)
					)
				)
			),
			spacerbox(size(1,10)),
			Button Box( "OK",
				<<setfunction(
					Function({t}, ColsUnique = Cunique << get items;ColsBy= Cby << get items)
				)
			),
			spacerbox(size(1,10)),
		)
	)
);

ccs= Expr(Col Cumulative Sum( 1));
for each ({col}, ColsUnique, Insert Into(ccs, Name Expr(As column(col))));
for each ({col}, ColsBy, Insert Into(ccs, Name Expr(As column(col))));
cs = Eval Expr(Col Sum( Expr(Eval Expr(Expr(Name Expr(ccs)) == 1 ))));
for each ({col}, ColsBy, Insert Into(cs, Name Expr(As column(col))));

Eval (Eval Expr(new column ("unique_"|| concat items (ColsUnique,"_"),
	Formula(Expr(Name Expr(cs))))))
	

... available at a single mouse click : )

[#5]

[removed] didn't show up at the right position.