Render done need to clean expression

expression.py

@@ -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")

render.py

@@ -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 

texRender.py

@@ -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