I am learning erlang recently and I have a question.
I have an equation like this (~(2+1)). I want to parse to polish notation? For eg.{unaryMin{add,2,1}}
How do I start?
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This one should help you: http://stackoverflow.com/a/7242955/4169859 – Łukasz Ptaszyński Feb 27 '15 at 07:33
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Your example is not in polish notation as it contains an infix operation (2+1). Do you want to *convert* the expression into polish notation? – Martin Törnwall Feb 27 '15 at 10:08
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There is alot materials but I want to show as tokenizeing – FireNewbie Feb 27 '15 at 17:10
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If you want to parse something, from a simple formula to a programming language, you should start by learning about grammar, language and Compiler-compiler. Learning how to parse and translate/interpret something to another format is a very common task for any programmer (pretty much everything has a compiler/interpreter, even you image viewer, web browser, etc ...) so it's very important to learn about those things.
For Erlang, LYSE got a chapter about making a reverse-polish notation calculator here, and for converting from an infix equation to a prefix/postfix one, you should read about Shunt-Yard algorithm. Erlang also have is own version of yacc & lex : yecc, leex.
Maeln
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