Update NumPyPrinter to give the minimum over the first axis.

[sbt4104]

References to other Issues or PRs

Fixes #18770
Fixes #18742

Brief description of what is fixed or changed

Added axis=0 at the end of the _print_Min() and _print_Max() to give minimum/maximum over the first axis of an array.
amin((x + 1,0.1x + 3,0.5x + 1)) got updated to amin((x + 1,0.1x + 3,0.5x + 1), axis=0).

Other comments

Please suggest changes.

Release Notes

• printing
  • Fix lambdify with Min/Max for arrays of more than one dimension

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• printing
  • Fix lambdify with Min for arrays of more than one dimension (#18774 by @sbt4104)

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#### References to other Issues or PRs
Fixes #18770

#### Brief description of what is fixed or changed

Added axis=0 at the end of the _print_Min() and _print_Max() to give minimum/maximum over the first axis of an array.
amin((x + 1,0.1*x + 3,0.5*x + 1)) got updated to amin((x + 1,0.1*x + 3,0.5*x + 1), axis=0).

#### Other comments 
Please suggest changes.

### Release Notes
<!-- BEGIN RELEASE NOTES -->
* printing
    - Fix lambdify with `Min` for arrays of more than one dimension
<!-- END RELEASE NOTES -->

Update

The release notes on the wiki have been updated.

[codecov]

Codecov Report

Merging #18774 into master will decrease coverage by 0.009%.
The diff coverage is n/a.

@@              Coverage Diff              @@
##            master    #18774       +/-   ##
=============================================
- Coverage   75.661%   75.651%   -0.010%     
=============================================
  Files          647       647               
  Lines       168420    168420               
  Branches     39681     39682        +1     
=============================================
- Hits        127429    127413       -16     
- Misses       35442     35454       +12     
- Partials      5549      5553        +4     

[sylee957]

Can you also add some tests?

[sbt4104]

I am adding it .

[sbt4104]

Lambdify only takes numpy array as an input, it discards regular python array.
import numpy is giving me error on Travis CI

[sylee957]

The reason that your tests are failing is because you have not made that as an optional dependency test.
You should use the import_module logic to skip the test depending whether numpy is intalled or not.
I'd better keep the string output test in test_pycode, because it can be tested outside of the environment setup.

[asmeurer]

Look at how the other lambdify tests are written, so that they skip the test if numpy is not available.

[asmeurer]

I fixed the release notes entry. Please keep them so they are relevant to end-users, not referencing implementation details.

[sbt4104]

I will keep that in mind