sympy.init_session() too magic for Jupyter notebook?

[Daniele Nicolodi]

Hello,

I'm trying to use sympy in a Jupyter notebook, however, it seems that
sympy.init_session() does too much magic. If I call it without
arguments it fails with this exception:

> ---------------------------------------------------------------------------
> MultipleInstanceError Traceback (most recent call last)
> <ipython-input-15-93c617afb26a> in <module>()
> ----> 1 sympy.init_session()
>
> /opt/local/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/sympy/interactive/session.py in init_session(ipython, pretty_print, order, use_unicode, use_latex, quiet, auto_symbols, auto_int_to_Integer, str_printer, pretty_printer, latex_printer, argv)
> 431 else:
> 432 ip = init_ipython_session(argv=argv, auto_symbols=auto_symbols,
> --> 433 auto_int_to_Integer=auto_int_to_Integer)
> 434
> 435 if V(IPython.__version__) >= '0.11':
>
> /opt/local/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/sympy/interactive/session.py in init_ipython_session(argv, auto_symbols, auto_int_to_Integer)
> 262 # don't draw IPython banner during initialization:
> 263 app.display_banner = False
> --> 264 app.initialize(argv)
> 265
> 266 if auto_symbols:
>
> <decorator-gen-112> in initialize(self, argv)
>
> /opt/local/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/traitlets/config/application.py in catch_config_error(method, app, *args, **kwargs)
> 85 """
> 86 try:
> ---> 87 return method(app, *args, **kwargs)
> 88 except (TraitError, ArgumentError) as e:
> 89 app.print_help()
>
> /opt/local/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/IPython/terminal/ipapp.py in initialize(self, argv)
> 315 self.init_path()
> 316 # create the shell
> --> 317 self.init_shell()
> 318 # and draw the banner
> 319 self.init_banner()
>
> /opt/local/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/IPython/terminal/ipapp.py in init_shell(self)
> 331 self.shell = self.interactive_shell_class.instance(parent=self,
> 332 profile_dir=self.profile_dir,
> --> 333 ipython_dir=self.ipython_dir, user_ns=self.user_ns)
> 334 self.shell.configurables.append(self)
> 335
>
> /opt/local/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/traitlets/config/configurable.py in instance(cls, *args, **kwargs)
> 421 raise MultipleInstanceError(
> 422 'Multiple incompatible subclass instances of '
> --> 423 '%s are being created.' % cls.__name__
> 424 )
> 425
>
> MultipleInstanceError: Multiple incompatible subclass instances of TerminalInteractiveShell are being created.
>

IPython is version 6.2.0, Sympy is version 1.1.1.

I tried playing with the ipython argument to init_session() but both
True and False values did not do much good (did not get something
usable). The strange thing is that I have a sympy working just fine in
a Jupyter notebook on a work machine where I use Anaconda (this machine
uses an macports instead). I don't know if Anaconda patches Sympy
somehow or if it uses an older version that does not have this problem.
I can check that tomorrow.

Looking at the code for init_session() it seems that the possibility of
it being called in an IPython session is not handled.

This bug report is about the same issue:

https://github.com/sympy/sympy/issues/13319

Thanks. Cheers,
Daniele

[will wray]

Same error on all my Sympy notebooks that use init_session(),

using the latest updated Anaconda versions (on Windows).

Does anyone have a workaround or alternative?

If there is a fix then any idea when it'll arrive in Anaconda?

Thanks, Will

[Aaron Meurer]

This issue is fixed in the development version. We are working on a release now and should have a release candidate out by the end of the month.

Aaron Meurer

--
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 https://groups.google.com/group/sympy.
To view this discussion on the web visit https://groups.google.com/d/msgid/sympy/a77796dd-f904-4c85-8d13-77e4d41a5808%40googlegroups.com.
For more options, visit https://groups.google.com/d/optout.