Convert keyword to real

[katgboykin]

I am new! I have researched-can't seem to put it all together. I want to place text on the screen (i.e. Trees) restrict user input to known factors (i.e. 20 40 100) take input multiply that by .06. My code works, but I need to add restrictions..can u help?

[_Tharwat]

(initget "20 40 100")
(setq st (getkword  "\n Specify number [20 40 100] :"))

 Read about the function initget and getkword .

Tharwat

[Kent1Cooper]

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@katgboykin wrote:
I am new! I have researched-can't seem to put it all together. I want to place text on the screen (i.e. Trees) restrict user input to known factors (i.e. 20 40 100) take input multiply that by .06. My code works, but I need to add restrictions..can u help?

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What _Tharwat said, and then for your mathematical calculation, you need to turn the resulting string into a number:

(* (atoi st) 0.06)

or (atof) would work, too.