Given the infix expression -190 + 20, what would the correct result look like as RPN? -190 + 20 == -190 20 + ? or.. -190 + 20 == 190 - 20 + ? Are the rules for unary operators (negative) the same a...

I am looking for algorithm postfix to infix notation which will produce the minimum number of the parentheses. I have found that but it will produce many, many parentheses: http://tajendrasengar....

Background: In traditional Reverse Polish Notation, all operators must have fixed lengths, which allows RPN to be easily evaluated and manipulated by code because every token, expression, and subex...

Let's say I have my %foo; Can I set keys foo, bar, baz to a b c by taking a slice and doing parallel assignment with postfix notation? %foo->@{qw/foo bar baz/} = qw/a b c/ I used this synt...

I was asked to convert 7-2+3 into post fix notation while no operator precedence or left to right or right to left was mentioned in the question and then I had to make tree using translation scheme...

I want to generate in Python all possible RPN (Reverse Polish notation) expressions, that use letters from an input list (such as ['a', 'b', 'c']) and contain operators ['+', '-', '*', '/']. My id...

so i have a binary tree and a postfix expression "6 2 * 3 /" what is the algo to put it in a tree? like, [/] / \ [*] [3] / \ [6] [2]

By use I mean its use in many calculators like HP35- My guesses (and confusions) are - postfix is actually more memory efficient -( SO post comments here ). (confusion - The evaluation algorit...

I'm trying to convert python math expressions to postfix notation using the AST python module. Here's what I got so far: import parser import ast from math import sin, cos, tan formulas = [ "1+2...

What would be a good way to evaluate a string(array, something) that contains a postfix expression(ex: 3 5 +) to check for validity?

Can this postfix expression can be evaluated? 6 2 3 + - 3 8 2 / + * 2 5 3 +

Ok so I have to read in a postfix expression from a file. The postfix expression must have spaces to separate each operator or operand. What I have so far works only if there is no spaces between t...

I was expecting the following snippet: var = "Not Empty" unless defined? var var # => nil to return "Not Empty", but I got nil. Any insight into why this is happening?

Given an input like this: 3+4+ Algorithm turns it in to 3 4 + + I can find the error when it's time to execute the postfix expression. But, is it possible to spot this during the conversion? (Wi...

I am trapped at work with a locked down pc. But I am trying to practice my Scala. I am using Ideone.com since I can't even install scalac... Anyway this is not compiling: class DPt(var name: Stri...

I've been looking at the wiki page: http://en.wikipedia.org/wiki/Shunting-yard_algorithm I've used the code example to build the first part, basically I can currently turn : 3 + 4 * 2 / ( 1 - 5 ...

I'm in love with Ruby. In this language all core functions are actually methods. That's why I prefer postfix notation – when the data, which I want to process is placed left from the body of anonym...

I'm writing what might not even be called a language in python. I currently have several operators: +, -, *, ^, fac, @, !!. fac computes a factorial, @ returns the value of a variable, !! sets a va...

Since this question is about the increment operator and speed differences with prefix/postfix notation, I will describe the question very carefully lest Eric Lippert discover it and flame me! (fur...

Here is a Python postfix notation interpreter which utilizes a stack to evaluate the expressions. Is it possible to make this function more efficient and accurate? #!/usr/bin/env python import ...

The following class is used by another program. When it is accessed, it throws a StackOverFlowError. This is part of a Postfix Calculator I have to do as a project at my university. Any help woul...

I've been mulling over creating a language that would be extremely well suited to creation of DSLs, by allowing definitions of functions that are infix, postfix, prefix, or even consist of multiple...