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Welcome to Chebfun Trac!

This part of the website is a focal point for users who are interested in being involved with the development of Chebfun code. It also serves as a portal for submitting bug reports and feature requests.

Chebfun uses  Trac in order to help organise all these issues. Trac works using a ticket system. Tickets are notes that summarise a problem or suggestion and are emailed to the developers upon creation. Once the issue has been dealt with, the ticket will be closed by one of the developers.

To learn how to create a new ticket for reporting a bug or requesting a new feature, see below.

Creating a new ticket is the most useful way to report bugs and to keep track of their progress. However, if you would rather, you can simply tell us about your bug by emailing

More information on how to help develop Chebfun can be found in the Developer Zone.


These features can each be accessed at any time from the Chebfun Trac site. To do so, click on the appropriate tab on the panel at the top of each page.

  • View Tickets -- List of all previously submitted tickets. If you are intending to submit a new ticket, we ask that you check here first to see if the issue has already been identified.

  • Browse Source -- Interface to the Subversion (SVN) repository of Chebfun code.
  • Road Map -- List of major milestones that we intend to implement before the next scheduled stable release. Contributors may add new milestones by clicking on the "Add new milestone" button at the bottom of the page.

Creating a new ticket

Before submitting a ticket, please check here first to see if your concern or suggestion has already been identified.

First [newticket/ open a new ticket], then complete the following information fields:

  • SUMMARY -- Try to give a pithy, but descriptive outline of the bug or feature request. For example, Axis limit problem in PLOT.
  • DESCRIPTION -- Please be as detailed as possible here. If you are submitting a bug report, it is best to include the Chebfun commands that caused the problem.
  • TYPE -- Select from bug / feature request / question.
  • SEVERITY -- Some judgement is required here. If you're unsure, it's probably best to just select Normal.
  • VERSION -- Provide details of the version of Chebfun you are working with, in particular the revision number, so we can check whether your bug has already been fixed in a subsequent patch.

The other fields are non-essential, though if you wish to fill them out, you may do so.

Further information

If you require more information or advice about any aspect of Trac or SVN, please contact the Chebfun developers at:

Please contact us with any questions and comments.
Copyright © 2011, The University of Oxford & The Chebfun Team.