Possible bug with MatrixSymbol and subs(titution)

[Nathan Thern]

Does this session illustrate a bug, or am I missing a concept here?

Jupyter console 5.0.0

Python 3.5.2 (v3.5.2:4def2a2901a5, Jun 25 2016, 22:01:18) [MSC v.1900 32 bit (Intel)]
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In [1]: import sympy

In [2]: sympy.__version__
Out[2]: '1.0'

In [3]: from sympy import *

In [4]: A=MatrixSymbol('A',1,3)

In [5]: B=MatrixSymbol('B',1,3)

In [6]: C=MatrixSymbol('C',1,3)

In [7]: E=A-B

In [8]: F=C[0,0]

In [9]: F.subs(C,E)
Out[9]: (-1)*B + A[0, 0]

In [10]:

I would think the output of the last command should be

(-1)*B[0,0] + A[0, 0]

[Aaron Meurer]

Yes, this is a bug (can you open an issue for it?). It looks like the
expression is correct, but the printer isn't putting parentheses
around the (-B + A).

Aaron Meurer

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[Nathan Thern]

On Friday, November 4, 2016 at 6:15:23 PM UTC-5, Aaron Meurer wrote:

Yes, this is a bug (can you open an issue for it?).

Done.

Issue #11821

 

[Francesco Bonazzi]

On Monday, 7 November 2016 16:01:53 UTC+1, Nathan Thern wrote:

Done.

Issue #11821

Put the link:

https://github.com/sympy/sympy/issues/11821