Thanks for the help.

I am not a LISP user. My mistake was not putting "cadr PT1" in brackets.

I have been using this .lsp file (downloaded from this site) for students to extract XYZ coordinates to be used in a CNC.program. I am trying to adapt the program to extract XZ coordinates for programs for a CNC lathe. The problem I am having is that the X values I get are radius, and I need diameter. I have not been able to find out how to multiply the polyline point value by 2.

Here is a clip of the section of the script

   (foreach PT1 listCOORDINATES ;all vertices
    (princ (strcat "\n" "X" (rtos (cadr PT1) 2 __PV_DP) __PV_Delimiter
                        "Z" (rtos (car PT1) 2 __PV_DP) )) ; display XY

For simplicity, the Y coordinate (cadr) is the X axis, and the X coordinate (car) is the Z axis.

I need the value of the Y coordinate to be multiplied by 2. Can anyone suggest how to do this?

Many thanks.