sympy/parsing/mathematica.py

   1 from re import match
   2 from sympy import sympify
   3
   4 def mathematica (s):
   5     return sympify(parse(s))
   6
   7 def parse (s):
   8     s = s.strip()
   9
  10     #Begin rules
  11     rules = (
  12     (r"\A(\w+)\[([^\]]+[^\[]*)\]\Z", #Function call
  13         lambda m: translateFunction(m.group(1)) + "(" + parse(m.group(2)) + ")" ),
  14
  15     (r"\((.+)\)\((.+)\)", #Parenthesized implied multiplication
  16         lambda m: "(" + parse(m.group(1)) + ")*(" + parse(m.group(2)) + ")" ),
  17
  18     (r"\A\((.+)\)\Z", #Parenthesized expression
  19         lambda m: "(" + parse(m.group(1)) + ")" ),
  20
  21     (r"\A(.*[\w\.])\((.+)\)\Z", #Implied multiplication - a(b)
  22         lambda m: parse(m.group(1)) + "*(" + parse(m.group(2)) + ")" ),
  23
  24     (r"\A\((.+)\)([\w\.].*)\Z", #Implied multiplication - (a)b
  25         lambda m: "(" + parse(m.group(1)) + ")*" + parse(m.group(2)) ),
  26
  27     (r"\A([\d\.]+)([a-zA-Z].*)\Z", #Implied multiplicatin - 2a
  28         lambda m: parse(m.group(1)) + "*" + parse(m.group(2)) ),
  29
  30     (r"\A([^=]+)([\^\-\*/\+=]=?)(.+)\Z", #Infix operator
  31         lambda m: parse(m.group(1)) + translateOperator(m.group(2)) + parse(m.group(3)) ))
  32     #End rules
  33
  34     for rule, action in rules:
  35         m = match(rule, s)
  36         if m:
  37             return action(m)
  38
  39     return s
  40
  41 def translateFunction (s):
  42     if s[0:3] == "Arc":
  43         return "a" + s[3:]
  44     return s.lower()
  45
  46 def translateOperator (s):
  47     dictionary = {'^':'**'}
  48     if s in dictionary:
  49         return dictionary[s]
  50     return s