nalgebra/src/traits/structure.rs

478 lines
13 KiB
Rust

//! Traits giving structural informations on linear algebra objects or the space they live in.
use std::f32;
use std::f64;
use std::num::{Int, Float};
use std::slice::{Iter, IterMut};
use std::ops::{Add, Sub, Mul, Div, Neg, Rem, Index, IndexMut};
use traits::operations::{RMul, LMul, Axpy, Transpose, Inv, Absolute};
use traits::geometry::{Dot, Norm, Orig};
/// Basic integral numeric trait.
pub trait BaseNum: Copy + Zero + One +
Add<Self, Output = Self> + Sub<Self, Output = Self> +
Mul<Self, Output = Self> + Div<Self, Output = Self> +
Rem<Self, Output = Self> + Neg<Output = Self> + PartialEq +
Absolute<Self> + Axpy<Self> {
}
/// Basic floating-point number numeric trait.
pub trait BaseFloat: Float + BaseNum {
/// Archimedes' constant.
fn pi() -> Self;
/// 2.0 * pi.
fn two_pi() -> Self;
/// pi / 2.0.
fn frac_pi_2() -> Self;
/// pi / 3.0.
fn frac_pi_3() -> Self;
/// pi / 4.0.
fn frac_pi_4() -> Self;
/// pi / 6.0.
fn frac_pi_6() -> Self;
/// pi / 8.0.
fn frac_pi_8() -> Self;
/// 1.0 / pi.
fn frac_1_pi() -> Self;
/// 2.0 / pi.
fn frac_2_pi() -> Self;
/// 2.0 / sqrt(pi).
fn frac_2_sqrtpi() -> Self;
/// Euler's number.
fn e() -> Self;
/// log2(e).
fn log2_e() -> Self;
/// log10(e).
fn log10_e() -> Self;
/// ln(2.0).
fn ln_2() -> Self;
/// ln(10.0).
fn ln_10() -> Self;
}
/// Traits of objects which can be created from an object of type `T`.
pub trait Cast<T> {
/// Converts an element of type `T` to an element of type `Self`.
fn from(t: T) -> Self;
}
/// Trait of matrices.
///
/// A matrix has rows and columns and are able to multiply them.
pub trait Mat<N, R, C>: Row<R> + Col<C> + RMul<R> + LMul<C> + Index<(usize, usize), Output = N> { }
impl<N, M, R, C> Mat<N, R, C> for M
where M: Row<R> + Col<C> + RMul<R> + LMul<C> + Index<(usize, usize), Output = N> {
}
/// Trait implemented by square matrices.
pub trait SquareMat<N, V>: Mat<N, V, V> +
Mul<Self, Output = Self> + Eye + Transpose + Diag<V> + Inv + Dim + One {
}
impl<N, V, M> SquareMat<N, V> for M
where M: Mat<N, V, V> + Mul<M, Output = M> + Eye + Transpose + Diag<V> + Inv + Dim + One {
}
/// Trait for constructing the identity matrix
pub trait Eye {
/// Return the identity matrix of specified dimension
fn new_identity(dim: usize) -> Self;
}
/// Additive identity.
pub trait Zero {
/// Returns the additive identity.
fn zero() -> Self;
/// Tests if `self` is exactly zero.
fn is_zero(&self) -> bool;
}
/// Multiplicative identity.
pub trait One {
/// Returns the multiplicative identity.
fn one() -> Self;
}
/// Types that have maximum and minimum value.
pub trait Bounded {
/// The minimum value.
#[inline]
fn min_value() -> Self;
/// The maximum value.
#[inline]
fn max_value() -> Self;
}
// FIXME: return an iterator instead
/// Traits of objects which can form a basis (typically vectors).
pub trait Basis {
/// Iterates through the canonical basis of the space in which this object lives.
fn canonical_basis<F: FnMut(Self) -> bool>(F);
/// Iterates through a basis of the subspace orthogonal to `self`.
fn orthonormal_subspace_basis<F: FnMut(Self) -> bool>(&Self, F);
/// Gets the ith element of the canonical basis.
fn canonical_basis_element(i: usize) -> Option<Self>;
}
/// Trait to access rows of a matrix or a vector.
pub trait Row<R> {
/// The number of column of `self`.
fn nrows(&self) -> usize;
/// Reads the `i`-th row of `self`.
fn row(&self, i: usize) -> R;
/// Writes the `i`-th row of `self`.
fn set_row(&mut self, i: usize, R);
// FIXME: add iterators on rows: this could be a very good way to generalize _and_ optimize
// a lot of operations.
}
/// Trait to access columns of a matrix or vector.
pub trait Col<C> {
/// The number of column of this matrix or vector.
fn ncols(&self) -> usize;
/// Reads the `i`-th column of `self`.
fn col(&self, i: usize) -> C;
/// Writes the `i`-th column of `self`.
fn set_col(&mut self, i: usize, C);
// FIXME: add iterators on columns: this could be a very good way to generalize _and_ optimize
// a lot of operations.
}
/// Trait to access part of a column of a matrix
pub trait ColSlice<C> {
/// Returns a view to a slice of a column of a matrix.
fn col_slice(&self, col_id: usize, row_start: usize, row_end: usize) -> C;
}
/// Trait to access part of a row of a matrix
pub trait RowSlice<R> {
/// Returns a view to a slice of a row of a matrix.
fn row_slice(&self, row_id: usize, col_start: usize, col_end: usize) -> R;
}
/// Trait of objects having a spacial dimension known at compile time.
pub trait Dim {
/// The dimension of the object.
fn dim(unused_mut: Option<Self>) -> usize;
}
/// Trait to get the diagonal of square matrices.
pub trait Diag<V> {
/// Creates a new matrix with the given diagonal.
fn from_diag(diag: &V) -> Self;
/// Sets the diagonal of this matrix.
fn set_diag(&mut self, diag: &V);
/// The diagonal of this matrix.
fn diag(&self) -> V;
}
/// The shape of an indexable object.
pub trait Shape<I>: Index<I> {
/// Returns the shape of an indexable object.
fn shape(&self) -> I;
}
/// This is a workaround of current Rust limitations.
///
/// It exists because the `I` trait cannot be used to express write access.
/// Thus, this is the same as the `I` trait but without the syntactic sugar and with a method
/// to write to a specific index.
pub trait Indexable<I, N>: Shape<I> + IndexMut<I, Output = N> {
#[deprecated = "use the Index `[]` overloaded operator instead"]
/// Reads the `i`-th element of `self`.
fn at(&self, i: I) -> N;
#[deprecated = "use the IndexMut `[]` overloaded operator instead"]
/// Writes to the `i`-th element of `self`.
fn set(&mut self, i: I, N);
/// Swaps the `i`-th element of `self` with its `j`-th element.
fn swap(&mut self, i: I, j: I);
/// Reads the `i`-th element of `self`.
///
/// `i` is not checked.
unsafe fn unsafe_at(&self, i: I) -> N;
/// Writes to the `i`-th element of `self`.
///
/// `i` is not checked.
unsafe fn unsafe_set(&mut self, i: I, N);
}
/// This is a workaround of current Rust limitations.
///
/// Traits of objects which can be iterated through like a vector.
pub trait Iterable<N> {
/// Gets a vector-like read-only iterator.
fn iter<'l>(&'l self) -> Iter<'l, N>;
}
/// This is a workaround of current Rust limitations.
///
/// Traits of mutable objects which can be iterated through like a vector.
pub trait IterableMut<N> {
/// Gets a vector-like read-write iterator.
fn iter_mut<'l>(&'l mut self) -> IterMut<'l, N>;
}
/*
* Vec related traits.
*/
/// Trait that relates a point of an affine space to a vector of the associated vector space.
#[deprecated = "This will be removed in the future. Use point + vector operations instead."]
pub trait VecAsPnt<P> {
/// Converts this point to its associated vector.
fn to_pnt(self) -> P;
/// Converts a reference to this point to a reference to its associated vector.
fn as_pnt<'a>(&'a self) -> &'a P;
}
/// Trait grouping most common operations on vectors.
pub trait NumVec<N>: Dim +
Sub<Self, Output = Self> + Add<Self, Output = Self> +
Mul<N, Output = Self> + Div<N, Output = Self> +
Neg<Output = Self> +
Index<usize, Output = N> +
Zero + PartialEq + Dot<N> + Axpy<N> {
}
/// Trait of vector with components implementing the `BaseFloat` trait.
pub trait FloatVec<N: BaseFloat>: NumVec<N> + Norm<N> + Basis {
}
/*
* Pnt related traits.
*/
/// Trait that relates a point of an affine space to a vector of the associated vector space.
pub trait PntAsVec<V> {
/// Converts this point to its associated vector.
fn to_vec(self) -> V;
/// Converts a reference to this point to a reference to its associated vector.
fn as_vec<'a>(&'a self) -> &'a V;
// NOTE: this is used in some places to overcome some limitations untill the trait reform is
// done on rustc.
/// Sets the coordinates of this point to match those of a given vector.
fn set_coords(&mut self, coords: V);
}
/// Trait grouping most common operations on points.
// XXX: the vector space element `V` should be an associated type. Though this would prevent V from
// having bounds (they are not supported yet). So, for now, we will just use a type parameter.
pub trait NumPnt<N, V>:
Copy +
PntAsVec<V> +
Dim +
Orig +
PartialEq +
Axpy<N> +
Sub<Self, Output = V> +
Neg<Output = Self> +
Mul<N, Output = Self> +
Div<N, Output = Self> +
Add<V, Output = Self> +
Index<usize, Output = N> { // FIXME: + Sub<V, Self>
}
/// Trait of points with components implementing the `BaseFloat` trait.
pub trait FloatPnt<N: BaseFloat, V: Norm<N>>: NumPnt<N, V> + Sized {
/// Computes the square distance between two points.
#[inline]
fn sqdist(&self, other: &Self) -> N {
(*self - *other).sqnorm()
}
/// Computes the distance between two points.
#[inline]
fn dist(&self, other: &Self) -> N {
(*self - *other).norm()
}
}
/*
*
*
* Some implementations for builtin types.
*
*
*/
// Zero and One
macro_rules! impl_zero_one(
($n: ty, $zero: expr, $one: expr) => {
impl Zero for $n {
#[inline]
fn zero() -> $n {
$zero
}
#[inline]
fn is_zero(&self) -> bool {
*self == $zero
}
}
impl One for $n {
fn one() -> $n {
$one
}
}
}
);
impl_zero_one!(f32, 0.0, 1.0);
impl_zero_one!(f64, 0.0, 1.0);
impl_zero_one!(i8, 0, 1);
impl_zero_one!(i16, 0, 1);
impl_zero_one!(i32, 0, 1);
impl_zero_one!(i64, 0, 1);
impl_zero_one!(isize, 0, 1);
impl_zero_one!(u8, 0, 1);
impl_zero_one!(u16, 0, 1);
impl_zero_one!(u32, 0, 1);
impl_zero_one!(u64, 0, 1);
impl_zero_one!(usize, 0, 1);
// Bounded
macro_rules! impl_bounded(
($n: ty, $min: expr, $max: expr) => {
impl Bounded for $n {
#[inline]
fn min_value() -> $n {
$min
}
#[inline]
fn max_value() -> $n {
$max
}
}
}
);
impl_bounded!(f32, Float::min_value(), Float::max_value());
impl_bounded!(f64, Float::min_value(), Float::max_value());
impl_bounded!(i8, Int::min_value(), Int::max_value());
impl_bounded!(i16, Int::min_value(), Int::max_value());
impl_bounded!(i32, Int::min_value(), Int::max_value());
impl_bounded!(i64, Int::min_value(), Int::max_value());
impl_bounded!(isize, Int::min_value(), Int::max_value());
impl_bounded!(u8, Int::min_value(), Int::max_value());
impl_bounded!(u16, Int::min_value(), Int::max_value());
impl_bounded!(u32, Int::min_value(), Int::max_value());
impl_bounded!(u64, Int::min_value(), Int::max_value());
impl_bounded!(usize, Int::min_value(), Int::max_value());
// BaseFloat
macro_rules! impl_base_float(
($n: ident) => {
impl BaseFloat for $n {
/// Archimedes' constant.
fn pi() -> $n {
$n::consts::PI
}
/// 2.0 * pi.
fn two_pi() -> $n {
$n::consts::PI_2
}
/// pi / 2.0.
fn frac_pi_2() -> $n {
$n::consts::FRAC_PI_2
}
/// pi / 3.0.
fn frac_pi_3() -> $n {
$n::consts::FRAC_PI_3
}
/// pi / 4.0.
fn frac_pi_4() -> $n {
$n::consts::FRAC_PI_4
}
/// pi / 6.0.
fn frac_pi_6() -> $n {
$n::consts::FRAC_PI_6
}
/// pi / 8.0.
fn frac_pi_8() -> $n {
$n::consts::FRAC_PI_8
}
/// 1.0 / pi.
fn frac_1_pi() -> $n {
$n::consts::FRAC_1_PI
}
/// 2.0 / pi.
fn frac_2_pi() -> $n {
$n::consts::FRAC_2_PI
}
/// 2.0 / sqrt(pi).
fn frac_2_sqrtpi() -> $n {
$n::consts::FRAC_2_SQRTPI
}
/// Euler's number.
fn e() -> $n {
$n::consts::E
}
/// log2(e).
fn log2_e() -> $n {
$n::consts::LOG2_E
}
/// log10(e).
fn log10_e() -> $n {
$n::consts::LOG10_E
}
/// ln(2.0).
fn ln_2() -> $n {
$n::consts::LN_2
}
/// ln(10.0).
fn ln_10() -> $n {
$n::consts::LN_10
}
}
}
);
impl BaseNum for i8 { }
impl BaseNum for i16 { }
impl BaseNum for i32 { }
impl BaseNum for i64 { }
impl BaseNum for isize { }
impl BaseNum for u8 { }
impl BaseNum for u16 { }
impl BaseNum for u32 { }
impl BaseNum for u64 { }
impl BaseNum for usize { }
impl BaseNum for f32 { }
impl BaseNum for f64 { }
impl_base_float!(f32);
impl_base_float!(f64);