XML documentation for Ordinary Least Squares trainer.

[codemzs]

towards #2522

[codecov]

Codecov Report

Merging #3405 into master will decrease coverage by <.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #3405      +/-   ##
==========================================
- Coverage   72.73%   72.73%   -0.01%     
==========================================
  Files         807      807              
  Lines      145206   145206              
  Branches    16230    16230              
==========================================
- Hits       105614   105613       -1     
+ Misses      35177    35176       -1     
- Partials     4415     4417       +2

Flag	Coverage Δ
#Debug	72.73% <ø> (-0.01%)	⬇️
#production	68.27% <ø> (ø)	⬆️
#test	88.98% <ø> (-0.01%)	⬇️

Impacted Files	Coverage Δ
...icrosoft.ML.Mkl.Components/MklComponentsCatalog.cs	65.71% <ø> (ø)	⬆️
...Microsoft.ML.Mkl.Components/OlsLinearRegression.cs	66.3% <ø> (ø)	⬆️
src/Microsoft.ML.Maml/MAML.cs	24.75% <0%> (-1.46%)	⬇️
...soft.ML.Data/DataLoadSave/Text/TextLoaderCursor.cs	84.7% <0%> (-0.41%)	⬇️
...soft.ML.TestFramework/DataPipe/TestDataPipeBase.cs	73.73% <0%> (-0.33%)	⬇️
...StandardTrainers/Standard/LinearModelParameters.cs	60.05% <0%> (-0.27%)	⬇️
...c/Microsoft.ML.FastTree/Utils/ThreadTaskManager.cs	100% <0%> (+20.51%)	⬆️

[shmoradims]

    /// </summary>

this change is missing. Options summary need to be updated too. #Resolved

---

Refers to: src/Microsoft.ML.Mkl.Components/OlsLinearRegression.cs:67 in 58e9889. [](commit_id = 58e9889, deletion_comment = False)

[shmoradims]