Evaluates mathematical and geometric expressions at the Command prompt or within a command.
CAL is an inline geometry calculator that evaluates point (vector), real, or integer expressions. The expressions can access existing geometry using the object snap functions such as CEN, END, and INS.
You can insert AutoLISP ® variables into the arithmetic expression and assign the value of the expression back to an AutoLISP variable. You can use these arithmetic and vector expressions in any command that expects points, vectors, or numbers. (Not available in AutoCAD LT.)