21 lines
637 B
Rust
21 lines
637 B
Rust
fn integral<F>(f: F, range: std::ops::Range<f64>, n_steps: u32) -> f64
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where F: Fn(f64) -> f64
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{
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let step_size = (range.end - range.start)/n_steps as f64;
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let mut integral = (f(range.start) + f(range.end))/2.;
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let mut pos = range.start + step_size;
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while pos < range.end {
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integral += f(pos);
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pos += step_size;
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}
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integral * step_size
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}
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fn main() {
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println!("{}", integral(|x| x.powi(3), 0.0..1.0, 100));
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println!("{}", integral(|x| 1.0/x, 1.0..100.0, 1000));
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println!("{}", integral(|x| x, 0.0..5000.0, 5_000_000));
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println!("{}", integral(|x| x, 0.0..6000.0, 6_000_000));
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}
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