[GSoC] Joints framework documentation

[tjstienstra]

References to other Issues or PRs

Brief description of what is fixed or changed

Fixes #21705.
Add general explanation about the joints framework within the physics/mechanics module.
Add images explaining the PinJoint and PrismaticJoint.
Add the JointsMethod docstring to the online documentation.

Other comments

Release Notes

• other
  • Add documentation about the joints framework in the physics/mechanics module.

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• other
  • Add documentation about the joints framework in the physics/mechanics module. (#23730 by @TJStienstra)

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#### Brief description of what is fixed or changed
Fixes #21705.
Add general explanation about the joints framework within the physics/mechanics module.
Add images explaining the `PinJoint` and `PrismaticJoint`.
Add the `JointsMethod` docstring to the online documentation.

#### Other comments


#### Release Notes

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  * Added a new solver for logarithmic equations.

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<!-- BEGIN RELEASE NOTES -->
* other
  * Add documentation about the joints framework in the physics/mechanics module.
<!-- END RELEASE NOTES -->

Update

The release notes on the wiki have been updated.

[sympy-bot]

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Hi, I am the SymPy bot (v167). I've noticed that some of your commits add or delete files. Since this is sometimes done unintentionally, I wanted to alert you about it.

This is an experimental feature of SymPy Bot. If you have any feedback on it, please comment at sympy/sympy-bot#75.

The following commits add new files:

• 7ea2a7b:
  • doc/src/modules/physics/mechanics/api/PinJoint.svg
  • doc/src/modules/physics/mechanics/api/PrismaticJoint.svg
• 09191ff:
  • doc/src/modules/physics/mechanics/joints.rst
• a712dea:
  • doc/src/modules/physics/mechanics/api/PinJoint.png
  • doc/src/modules/physics/mechanics/api/PrismaticJoint.png

If these files were added/deleted on purpose, you can ignore this message.

[tjstienstra]

@brocksam

[github-actions]

Benchmark results from GitHub Actions

Lower numbers are good, higher numbers are bad. A ratio less than 1
means a speed up and greater than 1 means a slowdown. Green lines
beginning with + are slowdowns (the PR is slower then master or
master is slower than the previous release). Red lines beginning
with - are speedups.

Significantly changed benchmark results (PR vs master)

Significantly changed benchmark results (master vs previous release)

       before           after         ratio
     [77f1d79c]       [806603dc]
     <sympy-1.10.1^0>                 
+      27.9±0.4μs         75.3±3μs     2.70  matrices.TimeMatrixExpression.time_MatAdd
+         129±3ms          224±4ms     1.74  sum.TimeSum.time_doit

Full benchmark results can be found as artifacts in GitHub Actions
(click on checks at the top of the PR).

[moorepants]

I'm seeing some issues in this image in the preview:

[moorepants]

I guess people could create these joints to just get static connections of bodies, so having a dynamicsymbol isn't strictly needed.

[moorepants]

Make both png and svg. Fix the few notes and this is good.

[moorepants]

I thought about this a bit more and may not regret merged the png file.

I'm not sure we have an other png's in the repo and I didn't check the size of this one. It is > 2 Mb.

[moorepants]

There are some more pngs, but this one is a bit excessive in size:

moorepants@nandi:sympy(master)$ find . -name *.png -exec ls -lh {} \;
-rw-rw-r-- 1 moorepants moorepants 8,7K mrt 30  2021 ./sympy/plotting/tests/test_region_or.png
-rw-rw-r-- 1 moorepants moorepants 7,8K mrt 30  2021 ./sympy/plotting/tests/test_region_not.png
-rw-rw-r-- 1 moorepants moorepants 9,8K mrt 30  2021 ./sympy/plotting/tests/test_region_xor.png
-rw-rw-r-- 1 moorepants moorepants 6,8K mrt 30  2021 ./sympy/plotting/tests/test_region_and.png
-rw-rw-r-- 1 moorepants moorepants 68K jul 15 09:39 ./doc/src/_static/sympylogo.png
-rw-rw-r-- 1 moorepants moorepants 164K mrt 30  2021 ./doc/src/_static/sympylogo_big.png
-rw-rw-r-- 1 moorepants moorepants 138K mrt 30  2021 ./doc/src/pics/consoleascii.png
-rw-rw-r-- 1 moorepants moorepants 119K mrt 30  2021 ./doc/src/pics/consoleunicode.png
-rw-rw-r-- 1 moorepants moorepants 37K mrt 30  2021 ./doc/src/pics/ipythonnotebook.png
-rw-rw-r-- 1 moorepants moorepants 239K mrt 30  2021 ./doc/src/pics/ipythonqtconsole.png
-rw-rw-r-- 1 moorepants moorepants 3,2K mrt 30  2021 ./doc/src/pics/pngview1.png
-rw-rw-r-- 1 moorepants moorepants 1,4M jul 15 09:40 ./doc/src/modules/physics/mechanics/api/PrismaticJoint.png
-rw-rw-r-- 1 moorepants moorepants 2,3M jul 15 09:40 ./doc/src/modules/physics/mechanics/api/PinJoint.png
-rw-rw-r-- 1 moorepants moorepants 68K jul 15 09:39 ./doc/src/modules/physics/mechanics/examples/multidof-holonomic.png
-rw-rw-r-- 1 moorepants moorepants 173K jul 15 09:40 ./doc/src/modules/physics/continuum_mechanics/truss_example.png
-rw-rw-r-- 1 moorepants moorepants 46K jul 15 09:39 ./doc/src/modules/physics/continuum_mechanics/ildshear.png
-rw-rw-r-- 1 moorepants moorepants 8,8K mrt 30  2021 ./doc/src/modules/physics/continuum_mechanics/allowed-sign-conventions.png
-rw-rw-r-- 1 moorepants moorepants 31K jul 15 09:39 ./doc/src/modules/physics/continuum_mechanics/ildreaction.png

[moorepants]

@tjstienstra I know you have a nice way of drawing these figures, but I think we need to stick to svg figures that are editable. We already seem to have a not so great precedent set with some images in the physics docs.

[tjstienstra]

Okay, than I'll go and work on some SVGs this week to replace them.