How to convert a string like "1+23-56" into a number

Question

Possible Duplicate:
Evaluating a math expression given in string form

How can I convert a string representing a math expression, like "1+23-56," into a number? I am trying to do this in Java.

It would help if you gave what language you were trying to do this in. — Jayson, Sep 06 '12 at 18:47
what technology are you using? Regular expressions are very useful in situations like these. They allow you to match the pattern and extract what you need. — sarsnake, Sep 06 '12 at 18:47
since you don't specify language, I'll assume you're using javascript. just pass it into eval() — MStodd, Sep 06 '12 at 18:47

score 1 · Answer 1 · answered Sep 06 '12 at 18:55

1

You would have to create your own language specification, with your own grammar and then implement it, there are several examples of how to write a language for a calculator.

The basic principle is to first do a syntax analisis, generate a syntactic tree and the parse it using your language rules, the semantic analisis.

Here are some examples:

answered Sep 06 '12 at 18:55

danielrvt

10,177
20
80
121

I am trying to do this in Java. – user1652919 Sep 06 '12 at 19:05

How to convert a string like "1+23-56" into a number

1 Answers1