How do I use a variable to reference a column in formula function?

Question

Hi, I need to create a new column by apply formula on two existing column. I want to reference column through a variable rather than direct referencing. Here is the code , but formula seems doesn't recognize Column(ColVar). Anyone could help me to fix it? Thanks in advance.

yCol = Column("weight");
xCol = Column("height");
Bivariate( Y( yCol ), X( xCol) );
colVar ="$weight";
dt = currentdatatable();
dt<<new column("sum", formula(column(ColVar)+:height));

Georg · Accepted Answer

Here is just another example using

eval(eval expr( expr ()))

but using the same strategy, implement the value of the variable into the formula.

Names Default To Here( 1 );

dt = Open( "$SAMPLE_DATA\Big Class.jmp" );

// get column names and show results
col_lst = dt << get column names();
my_cols= col_lst[4::5];
show(col_lst, my_cols);

// implement new formula
Eval( Eval Expr( dt << New Column( "sum of ", formula( sum(Expr(my_cols )) ) ) ) );