Struct Integrator

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pub struct Integrator { /* private fields */ }

Expand description

Numerical integration configuration.

Implementations§

Source §

impl Integrator

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pub const fn new(subintervals: usize) -> Self

Creates an integrator from a subinterval count.

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pub fn try_new(subintervals: usize) -> Result<Self, CalculusError>

Creates an integrator from a positive subinterval count.

§Errors

Returns CalculusError::ZeroSubintervals when subintervals == 0.

Examples found in repository ?

examples/basic_usage.rs (line 6)

3fn main() -> Result<(), use_calculus::CalculusError> {
4    let differentiator = Differentiator::try_new(1.0e-5)?;
5    let interval = IntegrationInterval::try_new(0.0, 1.0)?;
6    let integrator = Integrator::try_new(128)?;
7    let limit = LimitApproximator::try_new(1.0e-6, 1.0e-5)?;
8
9    let slope = differentiator.derivative_at(|x| x.powi(2), 3.0)?;
10    let area = integrator.simpson(|x| x * x, interval)?;
11    let sinc_limit = limit.at(
12        |x| {
13            if x == 0.0 { 1.0 } else { x.sin() / x }
14        },
15        0.0,
16    )?;
17
18    assert!((slope - 6.0).abs() < 1.0e-6);
19    assert!((area - (1.0 / 3.0)).abs() < 1.0e-6);
20    assert!((sinc_limit - 1.0).abs() < 1.0e-5);
21
22    Ok(())
23}

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pub fn validate(self) -> Result<Self, CalculusError>

Validates that the stored subinterval count is positive.

§Errors

Returns the same error variants as Self::try_new.

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pub const fn subintervals(&self) -> usize

Returns the stored subinterval count.

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pub fn trapezoidal<F>( self, function: F, interval: IntegrationInterval, ) -> Result<f64, CalculusError>
where F: FnMut(f64) -> f64,

Approximates a definite integral with the trapezoidal rule.

§Errors

Returns CalculusError when the interval or subinterval count is invalid, or when sampled evaluations are not finite.

Source

pub fn simpson<F>( self, function: F, interval: IntegrationInterval, ) -> Result<f64, CalculusError>
where F: FnMut(f64) -> f64,

Approximates a definite integral with Simpson’s rule.

§Errors

Returns CalculusError when the interval or subinterval count is invalid, when an odd number of subintervals is used, or when sampled evaluations are not finite.

Examples found in repository ?

examples/basic_usage.rs (line 10)

3fn main() -> Result<(), use_calculus::CalculusError> {
4    let differentiator = Differentiator::try_new(1.0e-5)?;
5    let interval = IntegrationInterval::try_new(0.0, 1.0)?;
6    let integrator = Integrator::try_new(128)?;
7    let limit = LimitApproximator::try_new(1.0e-6, 1.0e-5)?;
8
9    let slope = differentiator.derivative_at(|x| x.powi(2), 3.0)?;
10    let area = integrator.simpson(|x| x * x, interval)?;
11    let sinc_limit = limit.at(
12        |x| {
13            if x == 0.0 { 1.0 } else { x.sin() / x }
14        },
15        0.0,
16    )?;
17
18    assert!((slope - 6.0).abs() < 1.0e-6);
19    assert!((area - (1.0 / 3.0)).abs() < 1.0e-6);
20    assert!((sinc_limit - 1.0).abs() < 1.0e-5);
21
22    Ok(())
23}