Mailman 3 May 2019 - Matplotlib-devel

What is draw_path's transform's destination?
by Rob McDonald Sept. 24, 2019

Sept. 24, 2019

I'm implementing a custom path effect by inheriting from AbstractPathEffect and implementing draw_path as instructed here <https://matplotlib.org/api/patheffects_api.html#matplotlib.patheffects.Abst…>. That link references RenderBase.draw_path <https://matplotlib.org/api/backend_bases_api.html#matplotlib.backend_bases.…> to define the required interface. Unfortunately, I can't find anywhere in the associated documentation that tells me what the transform argument really entails. I've also read the transforms tutorial <https://matplotlib.org/tutorials/advanced/transforms_tutorial.html>, and while that explains the pipeline and all the intermediate transformations, it doesn't really settle what I have available to me in draw_path. It is clear that I can use it to transform coordinates from data to something -- but I don't know what to. For the big picture -- I am implementing a path effect to allow drawing hatched lines similar to this <https://www.mathworks.com/matlabcentral/fileexchange/29121-hatched-lines-an…>, which I did years ago in Matlab. Years before that, I've also done this in Java Graphics2D by implementing a custom stroke. (The Java approach is more applicable to the path effect approach, but I can't point to that code online anywhere.) Anyway, I have things mostly working -- and I am using the transform to go from data coordinates to something that looks orthogonal and reasonable on-screen. So, for minimum functionality, it works. However, I want to give the user the ability to control the length and spacing of the hatches -- which is in a coordinate system after the transformation is applied. So, in order to document this thing, I need to know what it is. Or, if there is a way to get intermediate stages of the transformation pipeline, that would work too. As for the user interface -- it seems to make the most sense to specify the hatch length and spacing in terms of something similar to a line width (typically points) or a marker size. I'm new to Python and matplotlib -- what is the Pythonic unit a user would expect to specify this in (and how do I achieve that with what is available in draw_path)? Thanks, Rob

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Matplotlib 2.2.2 - unclear license conditions for _png.cpp
by Arnold, Johann June 2, 2019

June 2, 2019

Dear Matplotlib developers, For one of our products we want to use Matplotlib 2.2.2. In order to distribute our product in a license compliant way we check the licenses of all OSS source code we are using. We do this on an file by file basis. For the file _png.cpp we have not been able to determine license situation. In file header we found the following text: // this code is heavily adapted from the paint license, which is in 4. // the file paint.license (BSD compatible) included in this 5. // distribution. TODO, add license file to MANIFEST.in and CVS 6. 7. /* For linux, png.h must be imported before Python.h because 8. png.h needs to be the one to define setjmp. 9. Undefining _POSIX_C_SOURCE and _XOPEN_SOURCE stops a couple 10. of harmless warnings. We could not find the file "paint.license", i.e. we do not know the correct license for _png.cpp. Can you please help us in order to get the correct license for _png.cpp Thanks a lot in advance and kind regards Johann Arnold Siemens AG Digital Industries Process Automation Software House Nbg DI PA CI R&D 3 Gleiwitzer Str. 555 90475 Nürnberg, Deutschland Tel.: +49 911 895-3162 Fax: +49 911 895-4010 mailto:johann.arnold@siemens.com www.siemens.com/ingenuityforlife<https://siemens.com/ingenuityforlife> [www.siemens.com/ingenuityforlife] Siemens Aktiengesellschaft: Vorsitzender des Aufsichtsrats: Jim Hagemann Snabe; Vorstand: Joe Kaeser, Vorsitzender; Roland Busch, Lisa Davis, Klaus Helmrich, Janina Kugel, Cedrik Neike, Michael Sen, Ralf P. Thomas; Sitz der Gesellschaft: Berlin und München, Deutschland; Registergericht: Berlin Charlottenburg, HRB 12300, München, HRB 6684; WEEE-Reg.-Nr. DE 23691322

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Weekly call moved
by Thomas Caswell May 30, 2019

May 30, 2019

Folks, Through NumFOCUS we now have access to a zoom account which we can use for our weekly meetings. Hopefully we will have less issues with this than we have been having with hangouts. As a reminder they are from 1500-1600 US Eastern (15:00-04) every Monday if you are interested please join! If people want to join, but this time / day does not work for you we can move it. The time can probably only move an hour or two either way (we need to get both Hawaii (UTC-10) and Central European Summer time (UTC+2) on the call) It seems to not be able to set up an infinity repeating meeting so this one is for 20 occurrences. Tom ---- Thomas Caswell is inviting you to a scheduled Zoom meeting. Topic: Matplotlib Weekly call Time: Jun 3, 2019 3:00 PM Eastern Time (US and Canada) Every week on Mon, 20 occurrence(s) Please download and import the following iCalendar (.ics) files to your calendar system. Weekly: https://zoom.us/meeting/384435716/ics?icsToken=5790d101e3242759366e1b5f95ff… Join Zoom Meeting https://zoom.us/j/384435716 One tap mobile +16468769923,,384435716# US (New York) +16699006833,,384435716# US (San Jose) Dial by your location +1 646 876 9923 US (New York) +1 669 900 6833 US (San Jose) +44 203 695 0088 United Kingdom +44 203 966 3809 United Kingdom +44 203 051 2874 United Kingdom +49 30 5679 5800 Germany +49 69 8088 3899 Germany +49 30 3080 6188 Germany +33 1 8288 0188 France +33 7 5678 4048 France +1 647 558 0588 Canada Meeting ID: 384 435 716 Find your local number: https://zoom.us/u/abafL44FHD -- Thomas Caswell tcaswell(a)gmail.com

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Matplotlib 3.1.1 plans
by Thomas Caswell May 24, 2019

May 24, 2019

Folks, We have a couple of major regressions in 3.1, to that end we are planning to do a 3.1.1 relatively soon (May 31 is the goal). Paul Ivanov has agreed to be the release manager for 3.1.1 Tom -- Thomas Caswell tcaswell(a)gmail.com

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LTGM github app
by Thomas Caswell May 19, 2019

May 19, 2019

Folks, I just installed the LGTM github app (moving us from the previous web-hook based version). I'm sorry if this is causing anyone else to get ~30 emails from them about the initial ingesting of each of our repositories. Tom -- Thomas Caswell tcaswell(a)gmail.com

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pydata events
by Thomas Caswell May 18, 2019

May 18, 2019

Folks, There are a number of pydata events coming up around the world ( https://pydata.org/events/ ). If you are interested in presenting a talk / tutorial or leading a sprint at any of the events please let me know and we can work with NumFOCUS to get it set up. Tom -- Thomas Caswell tcaswell(a)gmail.com

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REL: Matplotlib 3.1.0
by Thomas Caswell May 18, 2019

May 18, 2019

Folks, We are happy to announce the release of Matplotlib 3.1! Matplotlib 3.1 supports Python 3.6+. Highlights of this release include: - A helper method for scatter legends - Secondary axis support (ex, degrees and radians) - A concise date formatter - No longer requires a framework build of Python to use OSX backend - Major and minor ticks will no longer collide by default - A progress callback for animations - mplot3D is always registered - deprecated mlab functions have been removed - Many function calls have become stricter about invalid or ignored input For the full details see - whats new: https://matplotlib.org/users/whats_new.html - API changes: https://matplotlib.org/api/api_changes.html A big thank you to everyone who worked on this release including the 151 people contributed code [1] and the many more who reported issues. We are planning to have Matplotlib 3.2 released in September/October and Matplotlib 2.2.5 (the final release of the 2.2.x LTS series) in December. Tom [1] https://matplotlib.org/users/github_stats.html -- Thomas Caswell tcaswell(a)gmail.com

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REL: v3.1.0
by Thomas Caswell May 18, 2019

May 18, 2019

Folks, I (finally) tagged 3.1! Will announce do user list when wheels are built and up. A big thank you to every one on who worked on this! I am particularly thankful to David Stansby and Hannah Aizenman did much of the work colating the API and whats new documentation. Tom -- Thomas Caswell tcaswell(a)gmail.com

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Documentation Summit
by Hannah May 13, 2019

May 13, 2019

The Matplotlib development team is planning a 2 day documentation sprint / summit in Denver for late summer 2019 and have some travel funds. If you are interested in attending (either in person or calling in) please fill out http://bit.ly/docsum19 <https://docs.google.com/forms/d/11TvdN1nhPhEFyO3SrcXGyVk9PxKMBW1q0bhp61UPQJ…> The purpose of this summit is to: - write a work-plan for 9-12 months of work for a technical writer - including rough outlines, deliverable, and milestones - write a budget (technical writer + core dev time to manage / review) - write short grant to submit to foundations (4-6 pages, ~100k) To achieve these goals, the summit participants will identify problems with the Matplotlib documentation, including: - it is too big to effectively use (over 3k pages of content) - it is incomplete (many methods lack sufficient API documentation and examples) - there is no consistent voice through out the documentation - there is no clear path through the docs - the same content is serving many different audiences - existing users looking for API docs - new-to-python users looking for a "quick start" - new-to-programming/viz, but domain experts - new-to-visualization users starting from scratch - two main audiences: - scientists/user - trying to solve a specific problem as quickly as possible - developer writing visualization apps/ software - looking for detailed API docs and internal logic The participants will then develop a work plan for addressing these issues by hiring a technical writer with a mandate to: - audit and sort the existing documentation - potentially into tutorial, reference, topic and how-to guides - ensure complete coverage of API docs - de-duplicate the examples and tutorials - sort out what the per-requisites are and link appropriately - develop curated "paths" through examples / API doc - develop "quick reference" sheets - develop a template for domain specific intro material - implement several of these? - develop coding and documentation style guides - identify missing tutorials - scrape stackoverflow and otherwise engage with the community to determine what is missing and other such tasks. The technical writer will be expected to work with the developers to cover knowledge gaps. Please reply to this email with questions, comments, complaints, and suggestion and please fill out http://bit.ly/docsum19 <https://docs.google.com/forms/d/11TvdN1nhPhEFyO3SrcXGyVk9PxKMBW1q0bhp61UPQJ…> if you are interested in attending remotely or in person. Thanks, Hannah

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REL: Matplotilb v3.1.0rc2
by Thomas Caswell May 8, 2019

May 8, 2019

Folks, Just tagged rc2 which has a hand full of critical fixes - un-deprecated MaxNLocator default_params (this broke down-stream packages) - reverted un-intentional change to install the tests by default - fix saving non FuncAnimation animations - many documentation fixes - fixed bug in zorder of errorbars on barplots - fix bug that caused ticks to disappear in interactive use Will push to pypi as soon as all of the wheels are ready. Tom -- Thomas Caswell tcaswell(a)gmail.com

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