Opened 5 years ago
Last modified 5 years ago
#757 new defect
Need sqrt function
| Reported by: | Jiri Svoboda | Owned by: | |
|---|---|---|---|
| Priority: | major | Milestone: | |
| Component: | helenos/unspecified | Version: | mainline |
| Keywords: | Cc: | ||
| Blocker for: | Depends on: | ||
| See also: |
Description
This commit 516e7808c5e1e23b10a77bb1429054a16f6fedc3 removed sqrt and most other functions from libmath claiming they are "either very imprecise or downright broken" despite all math functions passing at least some tests.
Now I need sqrt for statistics computation.
Note:
See TracTickets
for help on using tickets.
The problem I see with the removed functions is that they were unused, and there was nothing that would instill confidence that they are even implemented correctly. No error analysis, not even a ballpark estimate of how close the result is to the exact value, no tests worth speaking of.
Admittedly, for statistics, you don't care very much about precision and behavior in uncommon cases, but I very much prefer the function not existing at all over a version that's less than perfect. Especially since the function has been implemented, analyzed and used for decades in other BSD-licensed code bases.