Is there any way to simplify (-12*x - 1)*(2*x3 + 3*x2 - 2*x - 5) + (-6*x2 - x - 
7)*(6*x2 + 6*x - 2) ? I want to get the final result ,not an intermediate one.





At 2014-10-17 22:27:44, "Chris Smith" <smi...@gmail.com> wrote:

The parser was fixed as indicated at 
http://stackoverflow.com/questions/26249993/6x2-x-72x33x2-2x-5-as-input-in-sympy


>>> from sympy.parsing.mathematica import mathematica as m
>>> m('(-6 * x**2 - x - 7) * (2 * x**3 + 3 * x**2 - 2 * x - 5)')
(-6*x**2 - x - 7)*(2*x**3 + 3*x**2 - 2*x - 5)
>>> _.diff(x)
(-12*x - 1)*(2*x**3 + 3*x**2 - 2*x - 5) + (-6*x**2 - x - 7)*(6*x**2 + 6*x - 2)





On Wednesday, October 8, 2014 8:42:16 AM UTC-5, Mateusz Paprocki wrote:Hi,

On 8 October 2014 12:05,  <redsto...@163.com> wrote:
> Is there any function in SymPy can take this TEX command as an input
>
> (-6x^2-x-7)(2x^3+3x^2-2x-5)
>
> to find the derivative?

I wanted to suggest a mathematica parser for this:

In [1]: import sympy.parsing.mathematica as m

In [2]: m.parse("(-6x^2-x-7)(2x^3+3x^2-2x-5)")
Out[2]: '(-6*x**2-x-7)*(2*x**3+3*x**2-2*x-5)'

In [3]: eval(_)
Out[3]:
⎛     2        ⎞ ⎛   3      2          ⎞
⎝- 6⋅x  - x - 7⎠⋅⎝2⋅x  + 3⋅x  - 2⋅x - 5⎠

But there is bug there and the above output requires the following patch:

diff --git a/sympy/parsing/mathematica.py b/sympy/parsing/mathematica.py
index f86d59a..eeb12f7 100644
--- a/sympy/parsing/mathematica.py
+++ b/sympy/parsing/mathematica.py
@@ -39,7 +39,7 @@ def parse(s):
         (r"\A\((.+)\)([\w\.].*)\Z",  # Implied multiplication - (a)b
         lambda m: "(" + parse(m.group(1)) + ")*" + parse(m.group(2))),

-        (r"\A([\d\.]+)([a-zA-Z].*)\Z",  # Implied multiplicatin - 2a
+        (r"\A([+-]?[\d\.]+)([a-zA-Z].*)\Z",  # Implied multiplicatin - 2a
         lambda m: parse(m.group(1)) + "*" + parse(m.group(2))),

         (r"\A([^=]+)([\^\-\*/\+=]=?)(.+)\Z",  # Infix operator

Mateusz

> --
> You received this message because you are subscribed to the Google Groups
> "sympy" group.
> To unsubscribe from this group and stop receiving emails from it, send an
> email to sympy+un...@googlegroups.com.
> To post to this group, send email to sy...@googlegroups.com.
> Visit this group at http://groups.google.com/group/sympy.
> To view this discussion on the web visit
> https://groups.google.com/d/msgid/sympy/04e0cbd4-5b6b-4418-8166-024a0729aff8%40googlegroups.com.
> For more options, visit https://groups.google.com/d/optout.


--
You received this message because you are subscribed to a topic in the Google 
Groups "sympy" group.
To unsubscribe from this topic, visit 
https://groups.google.com/d/topic/sympy/RoJ_o598B7Q/unsubscribe.
To unsubscribe from this group and all its topics, send an email to 
sympy+unsubscr...@googlegroups.com.
To post to this group, send email to sympy@googlegroups.com.
Visit this group at http://groups.google.com/group/sympy.
To view this discussion on the web visit 
https://groups.google.com/d/msgid/sympy/94765cae-9366-4e3c-a64c-d7694104f038%40googlegroups.com.
For more options, visit https://groups.google.com/d/optout.

-- 
You received this message because you are subscribed to the Google Groups 
"sympy" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to sympy+unsubscr...@googlegroups.com.
To post to this group, send email to sympy@googlegroups.com.
Visit this group at http://groups.google.com/group/sympy.
To view this discussion on the web visit 
https://groups.google.com/d/msgid/sympy/5f2010a.1ee40.149420210e4.Coremail.redstone-cold%40163.com.
For more options, visit https://groups.google.com/d/optout.

Reply via email to