use ndarray::*;
use num_traits::Zero;
use super::convert::*;
use super::error::*;
use super::lapack_traits::*;
use super::layout::*;
use super::types::*;
pub use super::lapack_traits::Diag;
pub trait SolveTriangular<A, S, D>
where
A: Scalar,
S: Data<Elem = A>,
D: Dimension,
{
fn solve_triangular(&self, UPLO, Diag, &ArrayBase<S, D>) -> Result<Array<A, D>>;
}
pub trait SolveTriangularInto<S, D>
where
S: DataMut,
D: Dimension,
{
fn solve_triangular_into(&self, UPLO, Diag, ArrayBase<S, D>) -> Result<ArrayBase<S, D>>;
}
pub trait SolveTriangularInplace<S, D>
where
S: DataMut,
D: Dimension,
{
fn solve_triangular_inplace<'a>(&self, UPLO, Diag, &'a mut ArrayBase<S, D>) -> Result<&'a mut ArrayBase<S, D>>;
}
impl<A, Si, So> SolveTriangularInto<So, Ix2> for ArrayBase<Si, Ix2>
where
A: Scalar,
Si: Data<Elem = A>,
So: DataMut<Elem = A> + DataOwned,
{
fn solve_triangular_into(&self, uplo: UPLO, diag: Diag, mut b: ArrayBase<So, Ix2>) -> Result<ArrayBase<So, Ix2>> {
self.solve_triangular_inplace(uplo, diag, &mut b)?;
Ok(b)
}
}
impl<A, Si, So> SolveTriangularInplace<So, Ix2> for ArrayBase<Si, Ix2>
where
A: Scalar,
Si: Data<Elem = A>,
So: DataMut<Elem = A> + DataOwned,
{
fn solve_triangular_inplace<'a>(
&self,
uplo: UPLO,
diag: Diag,
mut b: &'a mut ArrayBase<So, Ix2>,
) -> Result<&'a mut ArrayBase<So, Ix2>> {
let la = self.layout()?;
let a_ = self.as_allocated()?;
let lb = b.layout()?;
if !la.same_order(&lb) {
transpose_data(b)?;
}
let lb = b.layout()?;
unsafe { A::solve_triangular(la, lb, uplo, diag, a_, b.as_allocated_mut()?)? };
Ok(b)
}
}
impl<A, Si, So> SolveTriangular<A, So, Ix2> for ArrayBase<Si, Ix2>
where
A: Scalar,
Si: Data<Elem = A>,
So: DataMut<Elem = A> + DataOwned,
{
fn solve_triangular(&self, uplo: UPLO, diag: Diag, b: &ArrayBase<So, Ix2>) -> Result<Array2<A>> {
let b = replicate(b);
self.solve_triangular_into(uplo, diag, b)
}
}
impl<A, Si, So> SolveTriangularInto<So, Ix1> for ArrayBase<Si, Ix2>
where
A: Scalar,
Si: Data<Elem = A>,
So: DataMut<Elem = A> + DataOwned,
{
fn solve_triangular_into(&self, uplo: UPLO, diag: Diag, b: ArrayBase<So, Ix1>) -> Result<ArrayBase<So, Ix1>> {
let b = into_col(b);
let b = self.solve_triangular_into(uplo, diag, b)?;
Ok(flatten(b))
}
}
impl<A, Si, So> SolveTriangular<A, So, Ix1> for ArrayBase<Si, Ix2>
where
A: Scalar,
Si: Data<Elem = A>,
So: DataMut<Elem = A> + DataOwned,
{
fn solve_triangular(&self, uplo: UPLO, diag: Diag, b: &ArrayBase<So, Ix1>) -> Result<Array1<A>> {
let b = b.to_owned();
self.solve_triangular_into(uplo, diag, b)
}
}
pub trait IntoTriangular<T> {
fn into_triangular(self, UPLO) -> T;
}
impl<'a, A, S> IntoTriangular<&'a mut ArrayBase<S, Ix2>> for &'a mut ArrayBase<S, Ix2>
where
A: Zero,
S: DataMut<Elem = A>,
{
fn into_triangular(self, uplo: UPLO) -> &'a mut ArrayBase<S, Ix2> {
match uplo {
UPLO::Upper => {
for ((i, j), val) in self.indexed_iter_mut() {
if i > j {
*val = A::zero();
}
}
}
UPLO::Lower => {
for ((i, j), val) in self.indexed_iter_mut() {
if i < j {
*val = A::zero();
}
}
}
}
self
}
}
impl<A, S> IntoTriangular<ArrayBase<S, Ix2>> for ArrayBase<S, Ix2>
where
A: Zero,
S: DataMut<Elem = A>,
{
fn into_triangular(mut self, uplo: UPLO) -> ArrayBase<S, Ix2> {
(&mut self).into_triangular(uplo);
self
}
}