How to enter a variable in an INPUT ?

[What_Else]

(12-07-2019 10:14 PM)Dougggg Wrote:  If you do input as a string you can use the EXPR() command

EXPR("4*X");

Have I to put that in the code of the program, or when I use it ?
In fact, my program works, I would just like to know how to integrate variables into the calculation (i don't know if that's the good method)