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 )) ) ) ) );
```

Georg