Give float some examples #22030
Give float some examples #22030
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r? @huonw (rust_highfive has picked a reviewer for you, use r? to override) |
| @@ -75,16 +75,86 @@ mod cmath { | |||
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| #[stable(feature = "rust1", since = "1.0.0")] | |||
| impl Float for f32 { | |||
| /// Return `NaN` | |||
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I think this should be Returns NaN. (with an s and a ‘.’)—the indicative style is recommended over the imperative.
(Same thing for the others below.)
| #[inline] | ||
| fn classify(self) -> FpCategory { num::Float::classify(self) } | ||
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| /// Returns the mantissa, base 2 exponent, and sign as integers. The original |
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Previously didn't specify exponents base (2? 10? 7? e?). I had to figure out which one worked to recover the original number.
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You could document the trait itself rather than this specific implementation of it, no? |
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I don't mind documenting the trait. I was thinking there weren't any examples of traits being documented directly: |
mdinger
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Examples shouldn't break if you add a sign somewhere so prefer assigning to variables before using them: // Should prefer
let f = 2.0f64;
f.powi(2);
// over
2.0f64.powi(2);
// because
-2.0f64.powi(2);
// gets parsed as
-(2.0f64.powi(2));
// when the desired is
(-2.0f64).powi(2);
// but this works properly
let f = -2.0f64;
f.powi(2);Note: #22105 ran into this. |
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Yes, we usually document the trait, not the specific implementation. This seems good though, thanks! would you mind squashing? r=me after |
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Got a few left but sure. |
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Do you want me to just wait until you've got more? I assumed this was ready, if not, I'm happy to hold off. |
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Yeah. I've got another commit incoming. I'll squash after. I got most everything, maybe skipping deprecated and possibly a few unstable. I'll change the title from WIP when it's ready. |
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Cool, thank you |
mdinger
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@steveklabnik This depends on #22076 merging. It won't pass |
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| /// Returns the mantissa, base 2 exponent, and sign as integers, respectively. | ||
| /// The original number can be recovered by `sign * mantissa * 2 ^ exponent`. | ||
| /// The number is encoded with a scheme documented at | ||
| /// [IEEE floating point][IEEE-floating-point]. |
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How a float is encoded needs a good reference. This link is probably wrong and is mainly so I remember. Reposting so it's not hidden.
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Deferred to #22152 . Just referred to the float section of the reference for now.
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@steveklabnik Seems pretty good. Needs #22076 though so gotta wait until that lands. I'll do r= after that merges and |
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Rebased this commit back to tip. Should be mergeable. Didn't retest. |
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no rollup as this is a big diff |
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⌛ Testing commit 1a133f3 with merge b603823... |
Some examples for `std::num::Float` ~~This is WIP for making examples for `f32`. This probably won't pass `make tidy` and I'm not sure which `f32` needs documentation. rust-lang#22025 shows 2 sets of `f32` which seems split between `core` and `std`. I'm not sure which should be documented but I started doing a couple from `std`. Easy to move if that's where they go...~~ ~~Gotta build it eventually to actually see if the docs actually appear where I think they will or if I'm just disillusioned.~~ cc @steveklabnik
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💔 Test failed - auto-win-32-nopt-t |
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@bors: retry |
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⌛ Testing commit 1a133f3 with merge 4087e5b... |
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💔 Test failed - auto-win-32-nopt-t |
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@bors: retry |
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⌛ Testing commit 1a133f3 with merge 886aca4... |
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💔 Test failed - auto-win-64-nopt-t |
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@bors: retry |
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⌛ Testing commit 1a133f3 with merge c34229c... |
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💔 Test failed - auto-linux-64-nopt-t |
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@bors: retry |
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⌛ Testing commit 1a133f3 with merge 4b92061... |
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💔 Test failed - auto-linux-64-x-android-t |
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@bors: retry |
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⌛ Testing commit 1a133f3 with merge 77988b5... |
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💔 Test failed - auto-linux-64-opt |
Some examples for
std::num::FloatThis is WIP for making examples forf32. This probably won't passmake tidyand I'm not sure whichf32needs documentation. #22025 shows 2 sets off32which seems split betweencoreandstd. I'm not sure which should be documented but I started doing a couple fromstd. Easy to move if that's where they go...Gotta build it eventually to actually see if the docs actually appear where I think they will or if I'm just disillusioned.cc @steveklabnik