Ask Your Question

Getting a kernelspec warning when launching a notebook.

asked 2023-06-25 01:34:58 +0200

scribe36 gravatar image

updated 2023-06-27 15:52:54 +0200

FrédéricC gravatar image

I am on macOS Ventura 13.4.1 on a Macbook Air M2. sage --version returns SageMath version 10.0, Release Date: 2023-05-20.

Whenever I run sage -n, everything works fine but before anything is output, this line is printed (to stderr I think?)

WARNING:traitlets:Kernelspec name sagemath cannot be found!

I installed sage via Brew, i. e., brew install sage. Could someone help me get rid of this warning? Oh, and I don't have any outside Jupyter installed, which jupyter returns jupyter not found.

edit retag flag offensive close merge delete


Welcome to Ask Sage! Thank you for your question.

slelievre gravatar imageslelievre ( 2023-06-27 17:50:13 +0200 )edit

1 Answer

Sort by » oldest newest most voted

answered 2023-06-27 11:08:04 +0200

Marc Culler gravatar image

Installing via Homebrew has the same effect as installing directly from

It installs a Sage app in your /Applications folder.

One way to use it is then to double-click the resulting app.

Or from the terminal, run

open -a SageMath-10-0

instead of

sage -n

You will then get that nice little window which allows you to start a Jupyter notebook without any errors, in a correct environment, and with no technical gobbledygook such as:

To access the notebook, open this file in a browser:
    Or copy and paste one of these URLs:

Instead, the notebook manager will just open up in your default browser, ready to run.

edit flag offensive delete link more


This issue has now been fixed in the Sage 10.1 prerelease, and the fix will appear in the release.

Marc Culler gravatar imageMarc Culler ( 2023-07-13 21:21:37 +0200 )edit

Your Answer

Please start posting anonymously - your entry will be published after you log in or create a new account.

Add Answer

Question Tools

1 follower


Asked: 2023-06-25 01:34:58 +0200

Seen: 387 times

Last updated: Jun 27 '23