Implement the Gamma function with very low relative error #47
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
…lative error. This commit also extends that function to handle more special cases correctly.
Contributor
Author
|
It seems the tests fail because The tests compile and run fine on my local machine.
|
Contributor
Author
|
It may be that updating the |
…d of a const N array. According to godbolt.org both of these implementations result in the same assembly, but since this one is more flexible for the caller we should use this one.
Contributor
Author
|
If this PR is interesting then this code might also be interesting as it contains functions for computing the incomplete and complementary incomplete Gamma functions. |
I do not have a guarantee that wolfram alpha has it exactly right to the exact floating point number
Contributor
Author
|
Should the |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Hello!
I found this interesting implementation of the Gamma function by T. Fukushima (same person that published the algorithm I use in the
lambert_wcrate) in Fortran. It has a lower relative error than the current implementation (often within a single ulp), so I thought I could try implementing it in Rust.This PR implements this new Gamma function and makes the tests more stringent to show the reduced error.