calc.py

#  Copyright 2010, 2011 G24
#
#    This file is part of gpy.
#
#    gpy is free software: you can redistribute it and/or modify
#    it under the terms of the GNU General Public License as published by
#    the Free Software Foundation, either version 3 of the License, or
#    (at your option) any later version.
#
#    gpy is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#    GNU General Public License for more details.
#
#    You should have received a copy of the GNU General Public License
#    along with gpy.  If not, see <http://www.gnu.org/licenses/>.

import main

class mod_main(main.clisten):
    """Calc module."""
    def addcmds(self):
        self.name = "calc"
        self.cmds = {"rpn":"rpn"}
    def rpn(self): 
        '''Reverse Polish Notation Calc function.'''
        a = self.conn.recvinfo["message.params"].split(" ")
        self.stack = []
        for char in a:
            try:
                char = float(char)# if it succeeds, then char is a number
                self.stack.append(char)
            except Exception,e: #float(char) failed, it's nonsense or an operator
                try:
                    a = float(self.stack.pop()) #last
                    b = float(self.stack.pop()) #pre-last
                    if(char == "+"):
                        self.stack.append(a + b)
                    elif(char == "-"):
                        self.stack.append(b - a)
                    elif(char == "^"):
                        self.stack.append(pow(b,a))
                    elif(char == "*"):
                        self.stack.append(a * b)
                    elif(char == "/"):
                        self.stack.append(b / a)
                except Exception, e:
                    self.conn.reply(str(e))
                    return
        print self.stack
        try:
            self.conn.reply(str(self.stack[0]))
        except Exception, e:
            return