Added search functions in Ranges.v3
#288
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
titzer
reviewed
Oct 7, 2024
| @@ -76,4 +76,40 @@ component Ranges { | |||
| } | |||
| return i; | |||
| } | |||
| // Performs binary search and returns the index. | |||
There was a problem hiding this comment.
This code should follow the tab-per-indent level style of the surrounding Virgil code.
titzer
reviewed
Oct 8, 2024
| while (count > 0) { | ||
| var step = count >> 1; | ||
| var mid = start + step; | ||
| if (!lt(val, range[mid])) { start = mid + 1; count -= step + 1; } |
There was a problem hiding this comment.
I think there is a subtle distinction between !lt(x, y) and lt(y, x). I think this should code should use the latter. I think it should be accompanied with a comment that illustrates, like so:
// Assumes that {range} is sorted according to `lt` and returns the first element that is *greater* than `val`.
// e in | elem elem elem elem elem elem |
// lt(e, val) | true true false false false false |
// lt(val, e) | false false false true true true |
// ^
I think all three methods could use this comment.
| @@ -78,38 +78,38 @@ component Ranges { | |||
| } | |||
| // Performs binary search and returns the index. | |||
| def binarySearch<T>(range: Range<T>, val: T, lt: (T, T) -> bool) -> int { | |||
There was a problem hiding this comment.
I think we should name these three methods binarySearchEq, binarySearchLt, and binarySearchGt and comment them uniformly. See below.
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Outdated suggestions cannot be applied.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.
Added various binary search functions from the optimization PR in Wizard to
Ranges.v3.TODO: add tests in
RangesTest.v3