@David Wu - Welcome to Microsoft Q&A and thanks for reaching out to us.
For your queries above,
- doAzureParallel is no longer supported and no new features will be added anymore.
- RStudio is a data science IDE and they are working on a ML model. "https://github.com/Azure/doAzureParallel"
Hope this helps. and please feel free to reach out if you have any further questions.
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