student_t_cdf returning 0.0 when should be returning actual value
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Description
Hi, it appears student_t_cdf() returns 0.0 in cases where it shouldn't.
I have attached session output showing mismatched values - p-values using student_t_cdf() against R's t.test. Most match almost exactly but where they do not, student_t_cdf() appears to return exactly 0.0 rather than a computed value.
I have attached session output and a self-contained example (just source this into R). I hope it's not a coding mistake on my part, don't think so.
thanks
Fraser
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Research direction
Start by sourcing issue_git_R.txt in R and comparing its student_t_cdf() results with the attached output.txt and R's t.test values. Then locate the student_t_cdf() implementation and determine why some cases return exactly 0.0; the fix is done when those cases produce the expected nonzero values and the regression is covered by the project's relevant tests.
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Assessment
- Tech stack
- cpp, r
- Domain
- backend
- Issue type
- Bug
- Difficulty
- 3/5
- Estimated time
- 1-2 days
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 35/100