Scratch that - I got it working on one box, not on another. There must be more missing in the dependency chain. I'll see if I can identify what's missing.

Found it. Issue appears resolved by:

$ sudo dnf install -y python2-backports-shutil_get_terminal_size python2-psutil python2-simplegeneric python2-traitlets
$ sudo ln -s /usr/lib64/libSingular-4.1.0.so /usr/lib64/libSingular.so

corymbus\> sudo dnf repoquery --whatprovides /usr/lib64/libSingular.so
Last metadata expiration check: 1:52:44 ago on Fri 23 Jun 2017 11:43:28 AM EDT.
Singular-devel-0:4.1.0p2-1.fc26.x86_64
Singular-devel-0:4.1.0p3-2.fc26.x86_64

I can corroborate this problem on Fedora 26:

$ sage
┌────────────────────────────────────────────────────────────────────┐
│ SageMath version 7.6, Release Date: 2017-03-25                     │
│ Type "notebook()" for the browser-based notebook interface.        │
│ Type "help()" for help.                                            │
└────────────────────────────────────────────────────────────────────┘
Traceback (most recent call last):
  File "/usr/lib64/sagemath/local/bin/sage-ipython", line 7, in <module>
    from sage.repl.interpreter import SageTerminalApp
  File "/usr/lib64/python2.7/site-packages/sage/repl/interpreter.py", line 108, in <module>
    from sage.repl.prompts import SagePrompts, InterfacePrompts
  File "/usr/lib64/python2.7/site-packages/sage/repl/prompts.py", line 16, in <module>
    from IPython.terminal.prompts import Prompts
  File "/usr/lib64/sagemath/site-packages/IPython/__init__.py", line 48, in <module>
    from .core.application import Application
  File "/usr/lib64/sagemath/site-packages/IPython/core/application.py", line 25, in <module>
    from IPython.core import release, crashhandler
  File "/usr/lib64/sagemath/site-packages/IPython/core/crashhandler.py", line 28, in <module>
    from IPython.core import ultratb
  File "/usr/lib64/sagemath/site-packages/IPython/core/ultratb.py", line 128, in <module>
    from IPython.utils.terminal import get_terminal_size
  File "/usr/lib64/sagemath/site-packages/IPython/utils/terminal.py", line 22, in <module>
    from backports.shutil_get_terminal_size import get_terminal_size as _get_terminal_size
ImportError: No module named shutil_get_terminal_size


Unlike python2-traitlets, this problem doesn't go away when I install python2-backports-shutil_get_terminal_size.

Also something else: the /usr/bin/sage script uses `bash -i` as interpreter, which is kind of annoying, as it leaves a bunch of extraneous stuff on .bash_history.

IPython post-mortem report

{'commit_hash': u'5c9c918',
 'commit_source': 'installation',
 'default_encoding': 'ANSI_X3.4-1968',
 'ipython_path': '/usr/lib64/sagemath/site-packages/IPython',
 'ipython_version': '5.1.0',
 'os_name': 'posix',
 'platform': 'Linux-4.11.11-300.fc26.x86_64-x86_64-with-fedora-26-Twenty_Six',
 'sys_executable': '/usr/lib64/sagemath/local/bin/python',
 'sys_platform': 'linux2',
 'sys_version': '2.7.13 (default, Jun 26 2017, 10:20:05) \n[GCC 7.1.1 20170622 (Red Hat 7.1.1-3)]'}


Last line of .ipython/Sage_crash_report.txt is:

ImportError: No module named psutil




'dnf install python2-psutil' solves the issue for me.

Issue still present on F27, solved by:


dnf install python2-backports-shutil_get_terminal_size python2-psutil python2-simplegeneric python2-traitlets

Would someone add these dependencies please?

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Issue still present or got worse.

After an upgrade from F27 to F28, sagemath crashes. Missing dep is (at least) python2-cypari2.

Same here. Issue present on F28. Fresh install of sagemath
And here the same https://levlaz.org/installing-sage-math-on-fedora-28/


dnf -y install sagemath
sage 

=> Crash

$ grep -e "^ImportError"  /home/mambroz/.ipython/Sage_crash_report.txt
ImportError             Python 2.7.15: /usr/lib64/sagemath/local/bin/python
ImportError: No module named cypari2.gen


Workaround:
dnf -y install python2-cypari2

*** Bug 1572778 has been marked as a duplicate of this bug. ***

Checking in to confirm this is still a bug. How has this not been fixed in over a year??

I had to install lua and python2-cypari2 to get sagemath to install correctly.

(In reply to jman012345 from comment #10)
> Checking in to confirm this is still a bug. How has this not been fixed in
> over a year??

Confirming. This is still a bus as of August 26, 2018. Installing python2-cypari2 solved the issue. Thank you to teh SageMath group people who pointed this out to me.

This message is a reminder that Fedora 28 is nearing its end of life.
On 2019-May-28 Fedora will stop maintaining and issuing updates for
Fedora 28. It is Fedora's policy to close all bug reports from releases
that are no longer maintained. At that time this bug will be closed as
EOL if it remains open with a Fedora 'version' of '28'.

Package Maintainer: If you wish for this bug to remain open because you
plan to fix it in a currently maintained version, simply change the 'version' 
to a later Fedora version.

Thank you for reporting this issue and we are sorry that we were not 
able to fix it before Fedora 28 is end of life. If you would still like 
to see this bug fixed and are able to reproduce it against a later version 
of Fedora, you are encouraged  change the 'version' to a later Fedora 
version prior this bug is closed as described in the policy above.

Although we aim to fix as many bugs as possible during every release's 
lifetime, sometimes those efforts are overtaken by events. Often a 
more recent Fedora release includes newer upstream software that fixes 
bugs or makes them obsolete.

Seems to be fixed in Fedora 30. I was able to install and run sage without a problem after upgrading via a clean install.

Fedora 28 changed to end-of-life (EOL) status on 2019-05-28. Fedora 28 is
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