Searching Maximum value of each row across several column and name of source column

[#1]

Hi,

I'm trying to come up with a jsl script which can find max value of each row and the column name corresponding to the max value. I was able to find the max value across all the columns but need some advice to find the column name corresponding to the max value

Here's the code:

Names Default To Here( 1 );

dt = Current Data Table();
dt << Select Columns( 2 :: 14 );
col = dt << Get Selected Columns( );
val = dt:MaxVal << get values( Format( "Best", 12 ) );

dt:Maximum Value << Set Formula( Max(col) );
nc = (N Items( col ));



For( j = 1, j <= N Items( val ), j++,
	xxx = {};

	For( i = 1, i <= nc, i++,
		If( Contains( char(col[i]), val[j] ),
			Insert Into( xxx, char(col[i]) )
		)
	);
	Column( dt, 16 )[j] =  xxx;
);

[#2 · Accepted solution]

There are many ways of doing this. Below is one example which should get you what you need:

Names Default To Here(1);

dt = Open("$DOWNLOADS/Sample data.jmp");

col_names = (dt << Get Column Names("String"))[2::(N Cols() - 2)];

m = dt[0, col_names];

Column(dt, "Maximum Value") << Set Values(V Max(m`));

Column(dt, "Maximum Col Name") << Set Data Type("Character");
Column(dt, "Maximum Col Name") << Set Each Value(
	max_idx = Loc(m[Row(), 0], :Maximum value)[1];
	col_names[max_idx];
); 

Edit: Copy pasted correct script

Edit2: Second quite similar option:

Names Default To Here(1);

dt = Open("$DOWNLOADS/Sample data.jmp");
Column(dt, "Maximum Col Name") << Set Data Type("Character");

col_names = (dt << Get Column Names("String"))[2::(N Cols() - 2)];

Column(dt, "Maximum Value") << Set Each Value(Max(dt[Row(), col_names]));
Column(dt, "Maximum Col Name") << Set Each Value(
	// could use loc max, but as we need maximum value in column, we can just use that with Loc
	max_idx = Loc(dt[Row(), col_names], :Maximum value)[1];
	col_names[max_idx];
);

[#3]

@jthi Thanks. Your code finds max value across column it seems and I want to evaluate max value of each row across multiple columns. I am expecting the following results 

[#4]

I had copy-pasted some very weird script, I have now edited it to correct one

[#5 · Accepted solution]

Here is another way of solving the problem

Names Default To Here( 1 );

dt = Current Data Table();
dt << Select Columns( 2 :: 14 );
col = dt << Get Selected Columns( );

dt << new column("MaxVal", set each value(Max(col)));
dt << new column("MaxVal Column", character, set each value(char(col[loc(matrix(col),:MaxVal)[1]])));

[#6]

dt << new column("MaxVal Column", character, set each value(char( col[loc(As List(matrix(col)),:MaxVal)[1] ])));

Propose above correction to last line for JMP14 atleast: the matrix(col) returns a matrix and the loc function needs a list as first argument so the matrix needs to be converted into a list with "As list".

[#7]

Thanks for this Jim! Just used this on 250 columns. Hope you are doing well.
I am now a long way from Texas. Map.