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Merge pull request #77 from budziq/rand

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Added two more rand examples
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David Tolnay 2017-05-13 18:13:14 -07:00 • committed by GitHub
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46
src/basics.md
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@ -5,6 +5,8 @@
| [Read lines of strings from a file][ex-std-read-lines] | [![std-badge]][std] | [![cat-filesystem-badge]][cat-filesystem] |
| [Read and write integers in little-endian byte order][ex-byteorder-le] | [![byteorder-badge]][byteorder] | [![cat-encoding-badge]][cat-encoding] |
| [Generate random floating point numbers][ex-rand-float] | [![rand-badge]][rand] | [![cat-science-badge]][cat-science] |
| [Generate random numbers within a range][ex-rand-range] | [![rand-badge]][rand] | [![cat-science-badge]][cat-science] |
| [Generate random numbers with normal distribution][ex-rand-dist] | [![rand-badge]][rand] | [![cat-science-badge]][cat-science] |
| [Generate random values of a custom type][ex-rand-custom] | [![rand-badge]][rand] | [![cat-science-badge]][cat-science] |
@ -109,6 +111,47 @@ fn main() {
}
```
[ex-rand-range]: #ex-rand-range
<a name="ex-rand-range"></a>
## Generate random numbers within a range
[![rand-badge]][rand] [![cat-science-badge]][cat-science]
A random value within a range `[0, 10)` (not including `10`) is generated with [`Rng::gen_range`].
```rust
extern crate rand;
use rand::Rng;
fn main() {
let mut rng = rand::thread_rng();
println!("{}", rng.gen_range(0, 10));
}
```
[ex-rand-dist]: #ex-rand-dist
<a name="ex-rand-dist"></a>
## Generate random numbers with normal distribution
[![rand-badge]][rand] [![cat-science-badge]][cat-science]
[`Normal`] distribution with mean `3` and standard deviation `5`
is created. A random value is generated with [`IndependentSample::ind_sample`].
```rust
extern crate rand;
use rand::distributions::{Normal, IndependentSample};
fn main() {
let normal = Normal::new(3.0, 5.0);
let mut rng = rand::thread_rng();
let v = normal.ind_sample(&mut rng);
println!("{} is from a N(3, 25) distribution", v)
}
```
[ex-rand-custom]: #ex-rand-custom
<a name="ex-rand-custom"></a>
## Generate random values of a custom type
@ -174,3 +217,6 @@ fn main() {
[`File::open`]: https://doc.rust-lang.org/std/fs/struct.File.html#method.open
[`Lines`]: https://doc.rust-lang.org/std/io/struct.Lines.html
[`Write`]: https://doc.rust-lang.org/std/io/trait.Write.html
[`Normal`]: https://doc.rust-lang.org/rand/rand/distributions/normal/struct.Normal.html
[`IndependentSample::ind_sample`]: https://doc.rust-lang.org/rand/rand/distributions/trait.IndependentSample.html#tymethod.ind_sample
[`Rng::gen_range`]: https://doc.rust-lang.org/rand/rand/trait.Rng.html#method.gen_range

4
src/intro.md
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@ -23,6 +23,8 @@ community. It needs and welcomes help. For details see
| [Read lines of strings from a file][ex-std-read-lines] | [![std-badge]][std] | [![cat-filesystem-badge]][cat-filesystem] |
| [Read and write integers in little-endian byte order][ex-byteorder-le] | [![byteorder-badge]][byteorder] | [![cat-encoding-badge]][cat-encoding] |
| [Generate random floating point numbers][ex-rand-float] | [![rand-badge]][rand] | [![cat-science-badge]][cat-science] |
| [Generate random numbers within a range][ex-rand-range] | [![rand-badge]][rand] | [![cat-science-badge]][cat-science] |
| [Generate random numbers with normal distribution][ex-rand-dist] | [![rand-badge]][rand] | [![cat-science-badge]][cat-science] |
| [Generate random values on a custom type][ex-rand-custom] | [![rand-badge]][rand] | [![cat-science-badge]][cat-science] |
## [Encoding](encoding.html)
@ -133,6 +135,8 @@ Keep lines sorted.
[ex-log-syslog]: app.html#ex-log-syslog
[ex-rand-custom]: basics.html#ex-rand-custom
[ex-rand-float]: basics.html#ex-rand-float
[ex-rand-range]: basics.html#ex-rand-range
[ex-rand-dist]: basics.html#ex-rand-dist
[ex-rayon-iter-mut]: concurrency.html#ex-rayon-iter-mut
[ex-std-read-lines]: basics.html#ex-std-read-lines
[ex-toml-config]: encoding.html#ex-toml-config