[−][src]Crate min_max
min-max: max!
and min!
macros for Rust
Why?
Sometimes you want to find the maximum of a bunch of scalars. Usually you would write something like max(x1, max(x2, max(x3, x4)))
. The max!
macro provided by this crate simplifies that to max!(x1, x2, x3, x4)
. (Note, for an iterable data structure, you would use xx.iter().max()
).
Usage
Add this to your Cargo.toml
:
min-max = "0.1"
Then, for example:
use min_max::*; fn main() { let max = max!(1, 5, 7, 2, 4, 9, 3); assert_eq!(max, 9); let min = min!(1, 5, 7, 2, 4, 9, 3); assert_eq!(min, 1); let min_max = min_max!(1, 5, 7, 2, 4, 9, 3); assert_eq!(min_max, (min, max)); }
Does it work on floats?
Yep. But you need to use max_partial!
/min_partial!
use min_max::*; fn main() { let partial_max = max_partial!(1.8f64, 5.8, 7.8, 2.8, 4.8, 9.8, 3.8); assert!((9.8 - partial_max).abs() < 1e-5); let partial_min = min_partial!(1.8f64, 5.8, 7.8, 2.8, 4.8, 9.8, 3.8); assert!((1.8 - partial_min).abs() < 1e-5); }
What about NaN
?
Do not use when your data contains NaN
. When NaN
is at the end, NaN
is returned. Otherwise, the min/max excluding NaN
is returned.
use min_max::*; fn main() { let partial_max = max_partial!(1.8, 5.8, f64::NAN, 2.8, 4.8, 9.8, 3.8); assert!((9.8 - partial_max).abs() < 1e-5); let partial_max = max_partial!(1.8, 5.8, 2.8, 4.8, 9.8, 3.8, f64::NAN); assert!(partial_max.is_nan()); let partial_min = min_partial!(1.8, 5.8, f64::NAN, 2.8, 4.8, 9.8, 3.8); assert!((1.8 - partial_min).abs() < 1e-5); let partial_min = max_partial!(1.8, 5.8, 2.8, 4.8, 9.8, 3.8, f64::NAN); assert!(partial_min.is_nan()); }
Can I use custom types?
Sure, why not?
use min_max::*; #[derive(Debug, Ord, PartialOrd, Eq, PartialEq, Clone, Copy)] struct Point { x: u16, y: u16, } fn main() { let a = Point { x: 5, y: 8 }; let b = Point { x: 10, y: 92 }; let c = Point { x: 0, y: 3 }; let max = max!(a, b, c); assert_eq!(max, b); }
What's going on under the hood?
Well, max!(x1, x2, x3)
expands to:
std::cmp::max(x1, std::cmp::max(x2, std::cmp::max(x3)))
and so on. min!
works similarly, but with std::cmp::min
.
min_partial!
and max_partial
uses the min
and max
functions from the partial-min-max
crate.
Macros
max | Returns the maximum element of the arguments. |
max_partial | Returns the maximum element of the arguments. Uses |
min | Returns the minimum element of the arguments. |
min_max | Returns the minimum and maximum element of the arguments. |
min_max_partial | Returns the minimum and maximum element of the arguments. Uses |
min_partial | Returns the maximum element of the arguments. Uses |
Functions
max | |
min |