symbolic spline

[smichr]

References to other Issues or PRs

fixes #19262

Brief description of what is fixed or changed

Other comments

Release Notes

• functions
  • bsplines are more robust in terms of handling symbolic knots

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• functions
  • bsplines are more robust in terms of handling symbolic knots (#19272 by @smichr)

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#### References to other Issues or PRs
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fixes #19262

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


#### Other comments


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* functions
    * bsplines are more robust in terms of handling symbolic knots
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Update

The release notes on the wiki have been updated.

[codecov]

Codecov Report

Merging #19272 into master will decrease coverage by 0.039%.
The diff coverage is 80.000%.

@@              Coverage Diff              @@
##            master    #19272       +/-   ##
=============================================
- Coverage   75.649%   75.610%   -0.040%     
=============================================
  Files          651       651               
  Lines       169487    169478        -9     
  Branches     40021     40016        -5     
=============================================
- Hits        128216    128143       -73     
- Misses       35654     35726       +72     
+ Partials      5617      5609        -8     

[jksuom]

How about using a dummy with no assumptions when constructing the spline polynomials and replacing that with x only in the output?