define deg2rad and rad2deg for any Number #22811
Merged
Conversation
This file contains 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
|
Just by curiosity, why are all three methods needed instead of only the one added in this PR? |
musm
reviewed
Jul 14, 2017
| @@ -165,6 +165,8 @@ julia> deg2rad(90) | |||
| deg2rad(z::AbstractFloat) = z * (oftype(z, pi) / 180) | |||
| rad2deg(z::Real) = rad2deg(float(z)) | |||
| deg2rad(z::Real) = deg2rad(float(z)) | |||
| rad2deg(z::Number) = (z/pi)*180 | |||
| deg2rad(z::Number) = (z*pi)/180 | |||
There was a problem hiding this comment.
I think it would be better to have (z/180)*pi to avoid overflow in special cases here.
There was a problem hiding this comment.
@musm, that just makes it possible to underflow...
|
@jebej, the old methods are more efficient for real numbers because they only do one multiplication rather than one multiplication and one division. |
|
You mean that the |
|
@jebej, yes. (Look at |
|
Will merge soon as this seems uncontroversial. |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
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Outdated suggestions cannot be applied.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.
deg2radandrad2degwere previously defined only forReal, but there is no reason not to define them for anyNumbertype for completeness, and this could occasionally be useful as I commented on discourse.The fallback definitions added by this PR are somewhat suboptimal for
Complex, but I don't see this as a real problem (no pun intended). I can't imagine a performance-sensitive case where this would be applied to complex numbers without being combined with some much more expensive function likesin. And of course, optimized methods could be added later if there is a need.