postfix-notation

I read book today. It introduced algorithm about chaning from infix to postfix.. What is benefits? Thanks in advance. Well for one, you can easily evaluate a postfix expression in a single scan from left to right with the help of a stack, unlike evaluating infix expressions. and second, there is no need of the concept of parentheses and precedence rules etc. in a postfix expression. I think infix is really easy to understand for human. Postfix is the good way for machine to process. Please prefer: http://www.cs.man.ac.uk/~pjj/cs2121/fix.html An advanced example that also illustrates the

I need a function that takes an infix string (like "3 + 4 * 9"), and convert it to postfix (like "4 9 * 3 +"). I got it working until you throw in parentheses within parentheses. I've been working on it all day and can't figure out what I'm doing wrong- can someone with a fresh mind see it, maybe? I feel like I'm really close! Thanks! Here's the code: string ExpressionManager::infixToPostfix(string infixExpression) { cout << "itop Testing : " << infixExpression << endl; string posnums = "0123456789"; string posops = "+-*/%(){}[]"; string onlyops = "+-/%*"; string space = " "; string openbra =

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] To construct a tree from the expression, pretend you are evaluating it directly but construct trees instead of calculating numbers. (This trick works for many more things than postfix expressions.) Algorithm: Have a stack to store intermediate values (which are trees), and examine each token from left to right: If it is a number, turn it into a leaf node and push it on the stack. If it is an operator, pop two items from the stack, construct an operator node with

My lecturer gave me an assignment to create a program to convert and infix expression to postfix using Stacks. I've made the stack classes and some functions to read the infix expression. But this one function, called convertToPostfix(char * const inFix, char * const postFix) which is responsible to convert the inFix expression in the array inFix to the post fix expression in the array postFix using stacks, is not doing what it suppose to do. Can you guys help me out and tell me what I'm doing wrong? The following is code where the functions to convert from inFix to postFix is and

My code: val exitStatus = url #> outfile ! scala.sys.process : new URL("http://www.scala-lang.org/") #> new File("scala-lang.html") ! Warning: postfix operator ! should be enabled [warn] by making the implicit value scala.language.postfixOps visible. [warn] This can be achieved by adding the import clause 'import scala.language.postfixOps' [warn] or by setting the compiler option -language:postfixOps. [warn] See the Scaladoc for value scala.language.postfixOps for a discussion [warn] why the feature should be explicitly enabled. [warn] val exitStatus = url #> outfile ! [warn] ^ [warn] one

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 variable. The code is below. How would I go about writing a way to define functions in this simple language? EDIT: i updated the code! import sys, shlex, readline, os, string List, assign, call, add, sub, div, Pow, mul, mod, fac, duf, read,\ kill, clr, STO, RET, fib, curs = {}, "set", "get", "+", "-", "/", "^", "*",\ "%", "fact", "func", "read", "kill", "clear", ">", "@", "fib", "vars" def fact

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 anonymous processing function, for example: array.map{...} . I believe, that it has advantages in how easy is this code to read. But Mathetica, being functional (yeah, it can be procedural if you want) dictates a style, where Function name is placed left from the data. As we can see in its manuals, // is used only when it's some simple Function, without arguments, like list // MatrixForm . When Function