Start objecting expression
This commit is contained in:
Lafrite
parent
decffa6d75
commit
4e3f0a9b66
275
expression.py
275
expression.py
|
|
@ -8,182 +8,185 @@ class Expression(object):
|
|||
priority = {"*" : 3, "/": 3, "+": 2, "-":2, "(": 1}
|
||||
|
||||
def __init__(self, exp):
|
||||
""" Initiate the expression.
|
||||
""" Initiate the expression
|
||||
|
||||
:param exp: the expression. It can be a string or a list of tokens. It can be infix or postfix expression
|
||||
"""
|
||||
self._tokens = {}
|
||||
self._strings = {}
|
||||
if type(exp) == list:
|
||||
fix = self.get_fix(exp)
|
||||
self._tokens[fix] = exp
|
||||
elif type(exp) == str:
|
||||
tokens = self.parseExp(exp)
|
||||
fix = self.get_fix(tokens)
|
||||
self._tokens[fix] = tokens
|
||||
self._strings[fix] = exp
|
||||
self._exp = exp
|
||||
|
||||
def simplify(self):
|
||||
""" Generator which return steps for computing the expression """
|
||||
if self._exp == 0:
|
||||
yield "Zero!"
|
||||
else:
|
||||
raise ValueError("The expression needs to be a string or a list of token")
|
||||
self.children = Expression(self._exp - 1)
|
||||
yield "num: " + str(self._exp)
|
||||
yield self.children.simplify().next()
|
||||
|
||||
# ---------------------
|
||||
# String parsing
|
||||
## ---------------------
|
||||
## String parsing
|
||||
|
||||
# @classmethod ????
|
||||
def parseExp(self, exp):
|
||||
""" Parse the expression, ie tranform a string into a list of tokens
|
||||
## @classmethod ????
|
||||
#def parseExp(self, exp):
|
||||
# """ Parse the expression, ie tranform a string into a list of tokens
|
||||
|
||||
:param exp: The expression (a string)
|
||||
:returns: list of token
|
||||
# :param exp: The expression (a string)
|
||||
# :returns: list of token
|
||||
|
||||
"""
|
||||
return exp.split(" ")
|
||||
# """
|
||||
# return exp.split(" ")
|
||||
|
||||
# ---------------------
|
||||
# "fix" recognition
|
||||
## ---------------------
|
||||
## "fix" recognition
|
||||
|
||||
def get_fix(self, tokens):
|
||||
""" Give the "fix" of an expression
|
||||
infix -> A + B
|
||||
prefix -> + A B
|
||||
postfix -> A B +
|
||||
#def get_fix(self, tokens):
|
||||
# """ Give the "fix" of an expression
|
||||
# infix -> A + B
|
||||
# prefix -> + A B
|
||||
# postfix -> A B +
|
||||
|
||||
:param exp: the expression (list of token)
|
||||
:returns: the "fix" (infix, postfix, prefix)
|
||||
# :param exp: the expression (list of token)
|
||||
# :returns: the "fix" (infix, postfix, prefix)
|
||||
|
||||
"""
|
||||
if tokens[0] in "+-*/":
|
||||
return "prefix"
|
||||
elif token[0] not in "+-*/" ans token[1] not in "+-*/":
|
||||
return "postfix"
|
||||
else:
|
||||
return "infix"
|
||||
# """
|
||||
# if tokens[0] in "+-*/":
|
||||
# return "prefix"
|
||||
# elif token[0] not in "+-*/" ans token[1] not in "+-*/":
|
||||
# return "postfix"
|
||||
# else:
|
||||
# return "infix"
|
||||
|
||||
# ----------------------
|
||||
# Expressions - tokens getters
|
||||
## ----------------------
|
||||
## Expressions - tokens getters
|
||||
|
||||
def tokens(self, fix = "infix"):
|
||||
"""Get the list of tokens with the wanted fix
|
||||
#def tokens(self, fix = "infix"):
|
||||
# """Get the list of tokens with the wanted fix
|
||||
|
||||
:param fix: the fix wanted (infix default)
|
||||
:returns: list of tokens
|
||||
# :param fix: the fix wanted (infix default)
|
||||
# :returns: list of tokens
|
||||
|
||||
"""
|
||||
# Si ce fix n'a pas encore été enregistré
|
||||
if fix not in self._tokens:
|
||||
# Il peut venir de la version string
|
||||
if fix in self._string:
|
||||
self._tokens[fix] = self.parseExp(self._string[fix])
|
||||
# Sinon il faut le calculer à partir d'une autre forme
|
||||
else:
|
||||
fix_transfo = "to" + fix.capitalize()
|
||||
getattr(self,fix_transfo)()
|
||||
# """
|
||||
# # Si ce fix n'a pas encore été enregistré
|
||||
# if fix not in self._tokens:
|
||||
# # Il peut venir de la version string
|
||||
# if fix in self._string:
|
||||
# self._tokens[fix] = self.parseExp(self._string[fix])
|
||||
# # Sinon il faut le calculer à partir d'une autre forme
|
||||
# else:
|
||||
# fix_transfo = "to" + fix.capitalize()
|
||||
# getattr(self,fix_transfo)()
|
||||
|
||||
return self._tokens[fix]
|
||||
# return self._tokens[fix]
|
||||
|
||||
##### On en est là,il faudra faire attention à bien vérifier ce que les "to..." enregistre (string ou tokens)
|
||||
###### On en est là,il faudra faire attention à bien vérifier ce que les "to..." enregistre (string ou tokens)
|
||||
|
||||
def string(self, fix = "infix"):
|
||||
"""Get the string with the wanted fix
|
||||
#def string(self, fix = "infix"):
|
||||
# """Get the string with the wanted fix
|
||||
|
||||
:param fix: the fix wanted (infix default)
|
||||
:returns: the string representing the expression
|
||||
# :param fix: the fix wanted (infix default)
|
||||
# :returns: the string representing the expression
|
||||
|
||||
"""
|
||||
# Si ce fix n'a pas encore été enregistré
|
||||
if fix not in self._string:
|
||||
# Il peut venir de la version string
|
||||
if fix in self._tokens:
|
||||
self._string[fix] = self.parseExp(self._string[fix])
|
||||
# Sinon il faut le calculer à partir d'une autre forme
|
||||
else:
|
||||
fix_transfo = "to" + fix.capitalize()
|
||||
getattr(self,fix_transfo)()
|
||||
# """
|
||||
# # Si ce fix n'a pas encore été enregistré
|
||||
# if fix not in self._string:
|
||||
# # Il peut venir de la version string
|
||||
# if fix in self._tokens:
|
||||
# self._string[fix] = self.parseExp(self._string[fix])
|
||||
# # Sinon il faut le calculer à partir d'une autre forme
|
||||
# else:
|
||||
# fix_transfo = "to" + fix.capitalize()
|
||||
# getattr(self,fix_transfo)()
|
||||
|
||||
return self._string[fix]
|
||||
# return self._string[fix]
|
||||
#
|
||||
## ----------------------
|
||||
## "fix" tranformations
|
||||
|
||||
# ----------------------
|
||||
# "fix" tranformations
|
||||
#def toPostfix(self):
|
||||
# """ Transorm the expression into postfix form using the infix form"""
|
||||
# pass
|
||||
|
||||
def toPostfix(self):
|
||||
""" Transorm the expression into postfix form using the infix form"""
|
||||
pass
|
||||
#def toInfix(self):
|
||||
# """ Tranform the expression into infix form using postfix form"""
|
||||
# pass
|
||||
|
||||
def toInfix(self):
|
||||
""" Tranform the expression into infix form using postfix form"""
|
||||
pass
|
||||
## ---------------------
|
||||
## Tools for placing parenthesis in infix notation
|
||||
|
||||
# ---------------------
|
||||
# Tools for placing parenthesis in infix notation
|
||||
#def needPar(operande, operator, posi = "after"):
|
||||
# """ Says whether or not the operande needs parenthesis
|
||||
|
||||
def needPar(operande, operator, posi = "after"):
|
||||
""" Says whether or not the operande needs parenthesis
|
||||
# :param operande: the operande
|
||||
# :param operator: the operator
|
||||
# :param posi: "after"(default) if the operande will be after the operator, "before" othewise
|
||||
# :returns: bollean
|
||||
# """
|
||||
# if isNumber(operande) and "-" in operande:
|
||||
# return 1
|
||||
# elif not isNumber(operande):
|
||||
# # Si c'est une grande expression ou un chiffre négatif
|
||||
# stand_alone = get_main_op(operande)
|
||||
# # Si la priorité de l'operande est plus faible que celle de l'opérateur
|
||||
# minor_priority = self.priority[get_main_op(operande)] < self.priority[operator]
|
||||
# # Si l'opérateur est -/ pour after ou juste / pour before
|
||||
# special = (operator in "-/" and posi == "after") or (operator in "/" and posi == "before")
|
||||
|
||||
:param operande: the operande
|
||||
:param operator: the operator
|
||||
:param posi: "after"(default) if the operande will be after the operator, "before" othewise
|
||||
:returns: bollean
|
||||
"""
|
||||
if isNumber(operande) and "-" in operande:
|
||||
return 1
|
||||
elif not isNumber(operande):
|
||||
# Si c'est une grande expression ou un chiffre négatif
|
||||
stand_alone = get_main_op(operande)
|
||||
# Si la priorité de l'operande est plus faible que celle de l'opérateur
|
||||
minor_priority = self.priority[get_main_op(operande)] < self.priority[operator]
|
||||
# Si l'opérateur est -/ pour after ou juste / pour before
|
||||
special = (operator in "-/" and posi == "after") or (operator in "/" and posi == "before")
|
||||
# return stand_alone and (minor_priority or special)
|
||||
# else:
|
||||
# return 0
|
||||
#
|
||||
# J'#aime pas bien cette endroit faudrait que ce soit une méthode qui s'applique uniquement à l'expression en question (self) pas à n'importe quel string, ça serait plus propre.
|
||||
#def get_main_op(exp):
|
||||
# """ Gives the main operation of the expression
|
||||
|
||||
return stand_alone and (minor_priority or special)
|
||||
else:
|
||||
return 0
|
||||
# :param exp: the expression
|
||||
# :returns: the main operation (+, -, * or /) or 0 if the expression is only one element
|
||||
|
||||
# J'aime pas bien cette endroit faudrait que ce soit une méthode qui s'applique uniquement à l'expression en question (self) pas à n'importe quel string, ça serait plus propre.
|
||||
def get_main_op(exp):
|
||||
""" Gives the main operation of the expression
|
||||
# """
|
||||
# parStack = Stack()
|
||||
# tokenList = exp.split(" ")
|
||||
|
||||
:param exp: the expression
|
||||
:returns: the main operation (+, -, * or /) or 0 if the expression is only one element
|
||||
# if len(tokenList) == 1:
|
||||
# # Si l'expression n'est qu'un élément
|
||||
# return 0
|
||||
|
||||
"""
|
||||
parStack = Stack()
|
||||
tokenList = exp.split(" ")
|
||||
# main_op = []
|
||||
|
||||
if len(tokenList) == 1:
|
||||
# Si l'expression n'est qu'un élément
|
||||
return 0
|
||||
# for token in tokenList:
|
||||
# if token == "(":
|
||||
# parStack.push(token)
|
||||
# elif token == ")":
|
||||
# parStack.pop()
|
||||
# elif token in "+-*/" and parStack.isEmpty():
|
||||
# main_op.append(token)
|
||||
|
||||
main_op = []
|
||||
# return min(main_op, key = lambda s: priority[s])
|
||||
|
||||
for token in tokenList:
|
||||
if token == "(":
|
||||
parStack.push(token)
|
||||
elif token == ")":
|
||||
parStack.pop()
|
||||
elif token in "+-*/" and parStack.isEmpty():
|
||||
main_op.append(token)
|
||||
## ---------------------
|
||||
## Computing the expression
|
||||
|
||||
return min(main_op, key = lambda s: priority[s])
|
||||
#def compute(self):
|
||||
# """ Recursive method for computing as a student the expression
|
||||
# :returns: list of steps needed to reach the result
|
||||
|
||||
# ---------------------
|
||||
# Computing the expression
|
||||
# """
|
||||
# pass
|
||||
#
|
||||
#def doMath(op, op1, op2):
|
||||
# """Compute "op1 op op2"
|
||||
|
||||
def compute(self):
|
||||
""" Recursive method for computing as a student the expression
|
||||
:returns: list of steps needed to reach the result
|
||||
# :param op: operator
|
||||
# :param op1: first operande
|
||||
# :param op2: second operande
|
||||
# :returns: string representing the result
|
||||
|
||||
"""
|
||||
pass
|
||||
# """
|
||||
# return str(eval(op1 + op + op2))
|
||||
|
||||
def doMath(op, op1, op2):
|
||||
"""Compute "op1 op op2"
|
||||
|
||||
:param op: operator
|
||||
:param op1: first operande
|
||||
:param op2: second operande
|
||||
:returns: string representing the result
|
||||
|
||||
"""
|
||||
return str(eval(op1 + op + op2))
|
||||
if __name__ == '__main__':
|
||||
a = Expression(10)
|
||||
for i in a.simplify():
|
||||
print(i)
|
||||
|
||||
# -----------------------------
|
||||
# Reglages pour 'vim'
|
||||
|
|
|
|||
|
|
@ -0,0 +1,191 @@
|
|||
#!/usr/bin/env python
|
||||
# encoding: utf-8
|
||||
|
||||
|
||||
class Expression(object):
|
||||
"""A calculus expression. Today it can andle only expression with numbers later it will be able to manipulate unknown"""
|
||||
|
||||
priority = {"*" : 3, "/": 3, "+": 2, "-":2, "(": 1}
|
||||
|
||||
def __init__(self, exp):
|
||||
""" Initiate the expression.
|
||||
|
||||
:param exp: the expression. It can be a string or a list of tokens. It can be infix or postfix expression
|
||||
"""
|
||||
self._tokens = {}
|
||||
self._strings = {}
|
||||
if type(exp) == list:
|
||||
fix = self.get_fix(exp)
|
||||
self._tokens[fix] = exp
|
||||
elif type(exp) == str:
|
||||
tokens = self.parseExp(exp)
|
||||
fix = self.get_fix(tokens)
|
||||
self._tokens[fix] = tokens
|
||||
self._strings[fix] = exp
|
||||
else:
|
||||
raise ValueError("The expression needs to be a string or a list of token")
|
||||
|
||||
# ---------------------
|
||||
# String parsing
|
||||
|
||||
# @classmethod ????
|
||||
def parseExp(self, exp):
|
||||
""" Parse the expression, ie tranform a string into a list of tokens
|
||||
|
||||
:param exp: The expression (a string)
|
||||
:returns: list of token
|
||||
|
||||
"""
|
||||
return exp.split(" ")
|
||||
|
||||
# ---------------------
|
||||
# "fix" recognition
|
||||
|
||||
def get_fix(self, tokens):
|
||||
""" Give the "fix" of an expression
|
||||
infix -> A + B
|
||||
prefix -> + A B
|
||||
postfix -> A B +
|
||||
|
||||
:param exp: the expression (list of token)
|
||||
:returns: the "fix" (infix, postfix, prefix)
|
||||
|
||||
"""
|
||||
if tokens[0] in "+-*/":
|
||||
return "prefix"
|
||||
elif token[0] not in "+-*/" ans token[1] not in "+-*/":
|
||||
return "postfix"
|
||||
else:
|
||||
return "infix"
|
||||
|
||||
# ----------------------
|
||||
# Expressions - tokens getters
|
||||
|
||||
def tokens(self, fix = "infix"):
|
||||
"""Get the list of tokens with the wanted fix
|
||||
|
||||
:param fix: the fix wanted (infix default)
|
||||
:returns: list of tokens
|
||||
|
||||
"""
|
||||
# Si ce fix n'a pas encore été enregistré
|
||||
if fix not in self._tokens:
|
||||
# Il peut venir de la version string
|
||||
if fix in self._string:
|
||||
self._tokens[fix] = self.parseExp(self._string[fix])
|
||||
# Sinon il faut le calculer à partir d'une autre forme
|
||||
else:
|
||||
fix_transfo = "to" + fix.capitalize()
|
||||
getattr(self,fix_transfo)()
|
||||
|
||||
return self._tokens[fix]
|
||||
|
||||
##### On en est là,il faudra faire attention à bien vérifier ce que les "to..." enregistre (string ou tokens)
|
||||
|
||||
def string(self, fix = "infix"):
|
||||
"""Get the string with the wanted fix
|
||||
|
||||
:param fix: the fix wanted (infix default)
|
||||
:returns: the string representing the expression
|
||||
|
||||
"""
|
||||
# Si ce fix n'a pas encore été enregistré
|
||||
if fix not in self._string:
|
||||
# Il peut venir de la version string
|
||||
if fix in self._tokens:
|
||||
self._string[fix] = self.parseExp(self._string[fix])
|
||||
# Sinon il faut le calculer à partir d'une autre forme
|
||||
else:
|
||||
fix_transfo = "to" + fix.capitalize()
|
||||
getattr(self,fix_transfo)()
|
||||
|
||||
return self._string[fix]
|
||||
|
||||
# ----------------------
|
||||
# "fix" tranformations
|
||||
|
||||
def toPostfix(self):
|
||||
""" Transorm the expression into postfix form using the infix form"""
|
||||
pass
|
||||
|
||||
def toInfix(self):
|
||||
""" Tranform the expression into infix form using postfix form"""
|
||||
pass
|
||||
|
||||
# ---------------------
|
||||
# Tools for placing parenthesis in infix notation
|
||||
|
||||
def needPar(operande, operator, posi = "after"):
|
||||
""" Says whether or not the operande needs parenthesis
|
||||
|
||||
:param operande: the operande
|
||||
:param operator: the operator
|
||||
:param posi: "after"(default) if the operande will be after the operator, "before" othewise
|
||||
:returns: bollean
|
||||
"""
|
||||
if isNumber(operande) and "-" in operande:
|
||||
return 1
|
||||
elif not isNumber(operande):
|
||||
# Si c'est une grande expression ou un chiffre négatif
|
||||
stand_alone = get_main_op(operande)
|
||||
# Si la priorité de l'operande est plus faible que celle de l'opérateur
|
||||
minor_priority = self.priority[get_main_op(operande)] < self.priority[operator]
|
||||
# Si l'opérateur est -/ pour after ou juste / pour before
|
||||
special = (operator in "-/" and posi == "after") or (operator in "/" and posi == "before")
|
||||
|
||||
return stand_alone and (minor_priority or special)
|
||||
else:
|
||||
return 0
|
||||
|
||||
# J'aime pas bien cette endroit faudrait que ce soit une méthode qui s'applique uniquement à l'expression en question (self) pas à n'importe quel string, ça serait plus propre.
|
||||
def get_main_op(exp):
|
||||
""" Gives the main operation of the expression
|
||||
|
||||
:param exp: the expression
|
||||
:returns: the main operation (+, -, * or /) or 0 if the expression is only one element
|
||||
|
||||
"""
|
||||
parStack = Stack()
|
||||
tokenList = exp.split(" ")
|
||||
|
||||
if len(tokenList) == 1:
|
||||
# Si l'expression n'est qu'un élément
|
||||
return 0
|
||||
|
||||
main_op = []
|
||||
|
||||
for token in tokenList:
|
||||
if token == "(":
|
||||
parStack.push(token)
|
||||
elif token == ")":
|
||||
parStack.pop()
|
||||
elif token in "+-*/" and parStack.isEmpty():
|
||||
main_op.append(token)
|
||||
|
||||
return min(main_op, key = lambda s: priority[s])
|
||||
|
||||
# ---------------------
|
||||
# Computing the expression
|
||||
|
||||
def compute(self):
|
||||
""" Recursive method for computing as a student the expression
|
||||
:returns: list of steps needed to reach the result
|
||||
|
||||
"""
|
||||
pass
|
||||
|
||||
def doMath(op, op1, op2):
|
||||
"""Compute "op1 op op2"
|
||||
|
||||
:param op: operator
|
||||
:param op1: first operande
|
||||
:param op2: second operande
|
||||
:returns: string representing the result
|
||||
|
||||
"""
|
||||
return str(eval(op1 + op + op2))
|
||||
|
||||
# -----------------------------
|
||||
# Reglages pour 'vim'
|
||||
# vim:set autoindent expandtab tabstop=4 shiftwidth=4:
|
||||
# cursor: 16 del
|
||||
Loading…
Reference in New Issue