40 lines
1.1 KiB
Rust
40 lines
1.1 KiB
Rust
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#![cfg_attr(rustfmt, rustfmt_skip)]
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#[macro_use]
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extern crate approx; // for assert_relative_eq
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extern crate nalgebra as na;
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use na::{Matrix4, Matrix4x3, Vector4};
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fn main() {
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let a = Matrix4::new(
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1.0, 1.0, 2.0, -5.0,
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2.0, 5.0, -1.0, -9.0,
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2.0, 1.0, -1.0, 3.0,
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1.0, 3.0, 2.0, 7.0,
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);
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let mut b = Vector4::new(3.0, -3.0, -11.0, -5.0);
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let decomp = a.lu();
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let x = decomp.solve(&b).expect("Linear resolution failed.");
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assert_relative_eq!(a * x, b);
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/*
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* It is possible to perform the resolution in-place.
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* This is particularly useful to avoid allocations when
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* `b` is a `DVector` or a `DMatrix`.
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*/
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assert!(decomp.solve_mut(&mut b), "Linear resolution failed.");
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assert_relative_eq!(x, b);
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/*
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* It is possible to solve multiple systems
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* simultaneously by using a matrix for `b`.
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*/
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let b = Matrix4x3::new(
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3.0, 2.0, 0.0,
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-3.0, 0.0, 0.0,
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-11.0, 5.0, -3.0,
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-5.0, 10.0, 4.0,
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);
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let x = decomp.solve(&b).expect("Linear resolution failed.");
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assert_relative_eq!(a * x, b);
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}
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