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Render done need to clean expression

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lafrite
2013-12-08 21:02:19 +01:00
parent a7fb8844b0
commit ead4e15d92
3 changed files with 256 additions and 72 deletions
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89
expression.py
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@@ -8,6 +8,7 @@ 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}
TEXSYM = {"*" : " \\times ", "+" : " + " , "-" : " - "}
def __init__(self, exp):
""" Initiate the expression
@@ -191,11 +192,60 @@ class Expression(object):
def postfix_tokens(self, val):
self._postfix_tokens = val
# ----------------------
# Latex render
@classmethod
def texRender(cls, postfix_tokens):
"""@todo: Docstring for texRender
:param postfix_tokens: the postfix list of tokens to transform into infix form.
:returns: the latex render ready to insert into a maht environment
>>> Expression.post2in_fix([2, 5, '+', 1, '-', 3, 4, '*', '/'])
['( ', 2, '+', 5, '-', 1, ' )', '/', '( ', 3, '*', 4, ' )']
"\frac{2 + 5 - 1}{3 \times 4)"
>>> Expression.post2in_fix([2])
"2"
"""
operandeStack = Stack()
for token in postfix_tokens:
if cls.isOperator(token):
op2 = operandeStack.pop()
op1 = operandeStack.pop()
if token == "/":
res = "\\frac{" + str(op1) + "}{" + str(op2) + "}"
else:
if cls.needPar(op2, token, "after"):
op2 = "\\left( " + str(op2) + " \\right) "
if cls.needPar(op1, token, "before"):
op2 = "\\left( " + str(op1) + " \\right) "
res = str(op1) + cls.TEXSYM[token] + str(op2)
operandeStack.push(res)
else:
operandeStack.push(token)
# Manip pour gerer les cas similaires au deuxième exemple
infix_tokens = operandeStack.pop()
if type(infix_tokens) == list:
infix_tokens = flatten_list(infix_tokens)
elif cls.isNumber(infix_tokens):
infix_tokens = [infix_tokens]
return infix_tokens
# ----------------------
# "fix" tranformations
@classmethod
def in2post_fix(self, infix_tokens):
def in2post_fix(cls, infix_tokens):
""" From the infix_tokens list compute the corresponding postfix_tokens list
@param infix_tokens: the infix list of tokens to transform into postfix form.
@@ -215,9 +265,9 @@ class Expression(object):
while topToken != "(":
postfixList.append(topToken)
topToken = opStack.pop()
elif self.isOperator(token):
elif cls.isOperator(token):
# On doit ajouter la condition == str sinon python ne veut pas tester l'appartenance à la chaine de caractère.
while (not opStack.isEmpty()) and (self.PRIORITY[opStack.peek()] >= self.PRIORITY[token]):
while (not opStack.isEmpty()) and (cls.PRIORITY[opStack.peek()] >= cls.PRIORITY[token]):
postfixList.append(opStack.pop())
opStack.push(token)
else:
@@ -229,7 +279,7 @@ class Expression(object):
return postfixList
@classmethod
def post2in_fix(self, postfix_tokens):
def post2in_fix(cls, postfix_tokens):
""" From the postfix_tokens list compute the corresponding infix_tokens list
@param postfix_tokens: the postfix list of tokens to transform into infix form.
@@ -243,14 +293,14 @@ class Expression(object):
operandeStack = Stack()
for token in postfix_tokens:
if self.isOperator(token):
if cls.isOperator(token):
op2 = operandeStack.pop()
if self.needPar(op2, token, "after"):
if cls.needPar(op2, token, "after"):
op2 = ["( ", op2, " )"]
op1 = operandeStack.pop()
if self.needPar(op1, token, "before"):
if cls.needPar(op1, token, "before"):
op1 = ["( ", op1, " )"]
res = [op1, token, op2]
@@ -263,7 +313,7 @@ class Expression(object):
infix_tokens = operandeStack.pop()
if type(infix_tokens) == list:
infix_tokens = flatten_list(infix_tokens)
elif self.isNumber(infix_tokens):
elif cls.isNumber(infix_tokens):
infix_tokens = [infix_tokens]
return infix_tokens
@@ -272,7 +322,7 @@ class Expression(object):
# Tools for placing parenthesis in infix notation
@classmethod
def needPar(self, operande, operator, posi = "after"):
def needPar(cls, operande, operator, posi = "after"):
"""Says whether or not the operande needs parenthesis
:param operande: the operande
@@ -280,13 +330,13 @@ class Expression(object):
:param posi: "after"(default) if the operande will be after the operator, "before" othewise
:returns: bollean
"""
if self.isNumber(operande) and operande < 0:
if cls.isNumber(operande) and operande < 0:
return 1
elif not self.isNumber(operande):
elif not cls.isNumber(operande):
# Si c'est une grande expression ou un chiffre négatif
stand_alone = self.get_main_op(operande)
stand_alone = cls.get_main_op(operande)
# Si la priorité de l'operande est plus faible que celle de l'opérateur
minor_priority = self.PRIORITY[self.get_main_op(operande)] < self.PRIORITY[operator]
minor_priority = cls.PRIORITY[cls.get_main_op(operande)] < cls.PRIORITY[operator]
# Si l'opérateur est -/ pour after ou juste / pour before
special = (operator in "-/" and posi == "after") or (operator in "/" and posi == "before")
@@ -295,13 +345,16 @@ class Expression(object):
return 0
@classmethod
def get_main_op(self, tokens):
def get_main_op(cls, tokens):
"""Getting the main operation of the list of tokens
:param exp: the list of tokens
:returns: the main operation (+, -, * or /) or 0 if the expression is only one element
"""
print("tokens: ", tokens)
parStack = Stack()
if len(tokens) == 1:
@@ -315,10 +368,12 @@ class Expression(object):
parStack.push(token)
elif token == ")":
parStack.pop()
elif self.isOperator(token) and parStack.isEmpty():
elif cls.isOperator(token) and parStack.isEmpty():
main_op.append(token)
return min(main_op, key = lambda s: self.PRIORITY[s])
print("main_op", main_op)
return min(main_op, key = lambda s: cls.PRIORITY[s])
## ---------------------
## Computing the expression
@@ -368,7 +423,7 @@ class Expression(object):
def test(exp):
a = Expression(exp)
#for i in a.simplify():
for i in a.simplify(render = render):
for i in a.simplify(render = Expression.texRender):
print(i)
print("\n")

184
render.py Normal file
View File

@@ -0,0 +1,184 @@
#!/usr/bin/env python
# encoding: utf-8
from generic import Stack,flatten_list
from fraction import Fraction
class Render(object):
"""A class which aims to create render functions from three dictionnaries:
- op_infix: dict of caracters
- op_postfix: dict of 2 arguments functions
- other: dict of caracters
Those three dictionnaries while define how a postfix expression will be transform into a string.
"""
PRIORITY = {"*" : 3, "/": 3, "+": 2, "-":2, "(": 1}
def __init__(self, op_infix = {}, op_postfix = {}, other = {}):
"""Initiate the render
@param op_infix: the dictionnary of infix operator with how they have to be render
@param op_postfix: the dictionnary of postfix operator with how they have to be render
@param other: other caracters like parenthesis.
"""
self.op_infix = op_infix
self.op_postfix = op_postfix
self.other = other
# TODO: there may be issues with PRIORITY
self.operators = list(self.op_infix.keys()) + list(self.op_postfix.keys()) + list(self.other.keys())
def __call__(self, postfix_tokens):
"""Make the object acting like a function
:param postfix_tokens: the list of postfix tokens to be render
:returns: the render string
"""
operandeStack = Stack()
for token in postfix_tokens:
if self.isOperator(token):
op2 = operandeStack.pop()
if self.needPar(op2, token, "after"):
op2 = self.other["("] + str(op2) + self.other[")"]
op1 = operandeStack.pop()
if self.needPar(op1, token, "before"):
op1 = self.other["("] + str(op1) + self.other[")"]
if token in self.op_infix:
res = fstr(str(op1) + self.op_infix[token] + str(op2))
elif token in self.op_postfix:
res = fstr(self.op_postfix[token](str(op1), str(op2)))
# Trick to remember the main op when the render will be done!
res.mainOp = token
operandeStack.push(res)
else:
operandeStack.push(token)
# Manip pour gerer les cas similaires au deuxième exemple
infix_tokens = operandeStack.pop()
if type(infix_tokens) == list:
infix_tokens = flatten_list(infix_tokens)
elif self.isNumber(infix_tokens):
infix_tokens = [infix_tokens]
return infix_tokens
# ---------------------
# Tools for placing parenthesis in infix notation
def needPar(self, 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 self.isNumber(operande) and operande < 0:
return 1
elif not self.isNumber(operande):
# Si c'est une grande expression ou un chiffre négatif
stand_alone = self.get_main_op(operande)
# Si la priorité de l'operande est plus faible que celle de l'opérateur
minor_priority = self.PRIORITY[self.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
def get_main_op(self, tokens):
"""Getting the main operation of the list of tokens
:param exp: the list of tokens
:returns: the main operation (+, -, * or /) or 0 if the expression is only one element
"""
if hasattr(tokens, "mainOp"):
return tokens.mainOp
if len(tokens) == 1:
# Si l'expression n'est qu'un élément
return 0
parStack = Stack()
main_op = []
for token in tokens:
if token == "(":
parStack.push(token)
elif token == ")":
parStack.pop()
elif self.isOperator(token) and parStack.isEmpty():
main_op.append(token)
return min(main_op, key = lambda s: self.PRIORITY[s])
## ---------------------
## Recognize numbers and operators
def isNumber(self, exp):
"""Check if the expression can be a number which means that it is not a operator
:param exp: an expression
:returns: True if the expression can be a number and false otherwise
"""
return type(exp) == int or type(exp) == Fraction
def isOperator(self, exp):
"""Check if the expression is in self.operators
:param exp: an expression
:returns: boolean
"""
return (type(exp) == str and exp in self.operators)
class fstr(str):
"""Fake string - they are used to stock the main operation of an rendered expression"""
pass
txt_infix = {"+": " + ", "-": " - ", "*": " * ", "/" : " / "}
txt_postfix = {}
txt_other = {"(": "( ", ")": ") "}
txt_render = Render(txt_infix, txt_postfix, txt_other)
def texFrac(op1, op2):
if op1[0] == "(" and op1[-1] == ")":
op1 = op1[1:-1]
if op2[0] == "(" and op2[-1] == ")":
op2 = op2[1:-1]
return "\\frac{" + str(op1) + "}{" + str(op2) + "}"
tex_infix = {"+": " + ", "-": " - ", "*": " * "}
tex_postfix = {"/": texFrac}
tex_other = {"(": "( ", ")": " )"}
tex_render = Render(tex_infix, tex_postfix, tex_other)
if __name__ == '__main__':
#exp = [2, 5, '+', 1, '-', 3, 4, '*', '/']
#print(txt_render(exp))
exp = [2, 5, '+', 1, '-', 3, 4, '*', '/', 3, '+']
print(tex_render(exp))
# -----------------------------
# Reglages pour 'vim'
# vim:set autoindent expandtab tabstop=4 shiftwidth=4:
# cursor: 16 del

55
texRender.py
View File

@@ -1,55 +0,0 @@
#!/usr/bin/env python
# encoding: utf-8
from generic import Stack
def post2in_fix(postfix_tokens):
""" From the postfix_tokens list compute the corresponding infix_tokens list
@param postfix_tokens: the postfix list of tokens to transform into infix form. If nothing is set, it takes the value self.postfix_tokens
@return: the corresponding infix list of tokens if postfix_tokens is set. nothing otherwise but stock it in self.infix_tokens
>>> post2in_fix([2, 5, '+', 1, '-', 3, 4, '*', '/'])
['( ', 2, '+', 5, '-', 1, ' )', '/', '( ', 3, '*', 4, ' )']
"""
operandeStack = Stack()
for token in postfix_tokens:
if self.isOperator(token):
op2 = operandeStack.pop()
if self.needPar(op2, token, "after"):
op2 = ["( ", op2, " )"]
op1 = operandeStack.pop()
if self.needPar(op1, token, "before"):
op1 = ["( ", op1, " )"]
res = [op1, token, op2]
operandeStack.push(res)
else:
operandeStack.push(token)
infix_tokens = flatten_list(operandeStack.pop())
return infix_tokens
def textRender(postfix_tokens):
""" A text baser render
:param postfix_tokens: The postfix list of tokens
:returns: the text expression
"""
infix_tokens = post2in_fix(postfix_tokens)
return ' '.join(infix_tokens)
if __name__ == '__main__':
import doctest
doctest.testmod()
# -----------------------------
# Reglages pour 'vim'
# vim:set autoindent expandtab tabstop=4 shiftwidth=4:
# cursor: 16 del