Thread: Help Please: Detecting Operators in Input

  1. #1
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    Unhappy Help Please: Detecting Operators in Input

    Hi,

    I plan to make a program that finds variable values in compound equations. I have all the knowledge I need to do the equations myself but I do not know how to make my program recognize the entered equation as an equation. Furthermore, and most importantly, I need to know how to make the program enter each number as an individual number between operators. So this is what I need to do:

    x + 4 = 0, find 'x'.

    Except I don't want to do it, I want to enter it and have the computer do it.

    So if you can help anywhere from recognizing individual terms to recognizing and excecuting operators please respond.

    Thanks,
    Hatchet

  2. #2
    Registered User Noir's Avatar
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    That's hard. You'll be writing your own expression parser and evaluator, and it's not an afternoon project unless you keep it really simple. I'd say look into recursive descent parsing, expression trees, and postfix conversion and evaluation with stacks to get the skinny on how it works.

  3. #3
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    Thanks, Noir. I will research those things and try it out.

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