octave errors while using syms

**mm1379** · May 25th, 2020

Hello,
When I want to use e.g. syms x these two errors appear.

Code:

>> syms x
error: 'python_ipc_popen2' undefined near line 62 column 15
error: called from
    python_ipc_driver at line 62 column 13
    pycall_sympy__ at line 163 column 9
    valid_sym_assumptions at line 38 column 10
    assumptions at line 82 column 7
    syms at line 97 column 13

Code:

>> syms x
Traceback (most recent call last):
  File "<stdin>", line 4, in <module>
  File "<stdin>", line 12, in octoutput_drv
  File "<stdin>", line 55, in octoutput
  File "/home/smhk/.local/lib/python3.6/site-packages/sympy/__init__.py", line 677, in __getattr__
    return getattr(self.mod, name)
AttributeError: module 'sympy.core.compatibility' has no attribute 'integer_types'
error: Python exception: AttributeError: module 'sympy.core.compatibility' has no attribute 'integer_types'
    occurred while copying variables to Python.
    Try "sympref reset" and repeat your command?
    (consider filing an issue at https://github.com/cbm755/octsympy/issues)
error: called from
    pycall_sympy__ at line 191 column 5
    valid_sym_assumptions at line 38 column 10
    assumptions at line 82 column 7
    syms at line 97 column 13

**monkeybrain20122** · May 25th, 2020

From your output

Python exception: AttributeError: module 'sympy.core.compatibility' has no attribute 'integer_types'

Apparetly sympy breaks backward compatibility, so try to install an earlier version that works.

Code:

sudo pip3 install sympy==1.4

Now in octave

Code:

>> pkg load symbolic
>> sym x
Symbolic pkg v2.9.0: Python communication link active, SymPy v1.4.
ans = (sym) x
>>

Ubuntu20.04, octave 5.2.0

P.S. I presume you are using Ubuntu 20.04, octave 5.2.0 (it is a good idea to tell people your ubuntu and software versions when you ask for help) and you installed sympy from the repo, which is version 1.5.x. You don't need to remove sympy from repo as it maybe a dependency of other things you installed with apt. pip installs sympy in /usr/local/lib which take precedence over the one installed by apt in /usr/lib at run time.

**mm1379** · May 25th, 2020

Thanks a lot.+1
It is working well know

P.S I am using octave4.2.2 and ubuntu18.04

**monkeybrain20122** · May 26th, 2020

I have tested that symbolic works with sympy 1.5 as well but not 1.6. Since you are in 18.04 so your repo's sympy may be too old rather than too new.

If your problem is solved please go to thread tools and mark the thread as solved.

**chessbucket** · July 7th, 2020

This solved my issue.

Originally Posted by monkeybrain20122

From your output

Apparetly sympy breaks backward compatibility, so try to install an earlier version that works.

Code:

sudo pip3 install sympy==1.4

Now in octave

Code:

>> pkg load symbolic
>> sym x
Symbolic pkg v2.9.0: Python communication link active, SymPy v1.4.
ans = (sym) x
>>

Ubuntu20.04, octave 5.2.0

P.S. I presume you are using Ubuntu 20.04, octave 5.2.0 (it is a good idea to tell people your ubuntu and software versions when you ask for help) and you installed sympy from the repo, which is version 1.5.x. You don't need to remove sympy from repo as it maybe a dependency of other things you installed with apt. pip installs sympy in /usr/local/lib which take precedence over the one installed by apt in /usr/lib at run time.