mlx_rs/ops/

shapes.rs

use mlx_internal_macros::generate_macro;
use smallvec::SmallVec;

use crate::{
    constants::DEFAULT_STACK_VEC_LEN,
    error::Result,
    utils::{guard::Guarded, IntoOption, VectorArray},
    Array, Axes, Stream,
};

static EMPTY_AXES_DUMMY: [i32; 1] = [0];

/// Options controlling contiguous layout materialization.
#[derive(Debug, Clone, Copy, Default, PartialEq, Eq)]
pub struct ContiguousOptions {
    /// Permit MLX to retain a column-major layout when it is already suitable.
    pub allow_col_major: bool,
}

impl Array {
    /// Return an array that is row-major contiguous after evaluation.
    ///
    /// MLX may share the input buffer when it is already suitable.
    pub fn contiguous(&self) -> Result<Array> {
        self.contiguous_with_options(ContiguousOptions::default())
    }

    /// Materialize a contiguous array according to `options`.
    ///
    /// Allowing column-major layout does not force it and does not guarantee that the result can
    /// be borrowed with [`Array::try_as_slice`].
    pub fn contiguous_with_options(&self, options: ContiguousOptions) -> Result<Array> {
        let stream = Stream::thread_local_or_default();
        Array::try_from_op(|res| unsafe {
            mlx_sys::mlx_contiguous(
                res,
                self.as_ptr(),
                options.allow_col_major,
                stream.as_ref().as_ptr(),
            )
        })
    }

    /// Reverse elements along selected axes.
    ///
    /// `Axes::All` reverses every axis, while an explicitly empty axis list is an identity.
    ///
    /// ```rust
    /// use mlx_rs::{array, Axes};
    ///
    /// let output = array!([[1, 2], [3, 4]]).flip(Axes::Axis(-1)).unwrap();
    /// assert_eq!(output.shape(), &[2, 2]);
    /// ```
    pub fn flip(&self, axes: Axes) -> Result<Array> {
        let stream = Stream::thread_local_or_default();
        match axes {
            Axes::All => Array::try_from_op(|res| unsafe {
                mlx_sys::mlx_flip(res, self.as_ptr(), stream.as_ref().as_ptr())
            }),
            Axes::Axis(axis) => Array::try_from_op(|res| unsafe {
                mlx_sys::mlx_flip_axis(res, self.as_ptr(), axis, stream.as_ref().as_ptr())
            }),
            Axes::Axes(axes) => {
                let axes_ptr = if axes.is_empty() {
                    EMPTY_AXES_DUMMY.as_ptr()
                } else {
                    axes.as_ptr()
                };
                Array::try_from_op(|res| unsafe {
                    mlx_sys::mlx_flip_axes(
                        res,
                        self.as_ptr(),
                        axes_ptr,
                        axes.len(),
                        stream.as_ref().as_ptr(),
                    )
                })
            }
        }
    }

    /// Split an array along `axis` and squeeze that axis from every output.
    ///
    /// A zero-length selected axis returns an empty vector.
    ///
    /// ```rust
    /// use mlx_rs::array;
    ///
    /// let parts = array!([[1, 2], [3, 4]]).unstack(0).unwrap();
    /// assert_eq!(parts.len(), 2);
    /// assert_eq!(parts[0].shape(), &[2]);
    /// ```
    pub fn unstack(&self, axis: i32) -> Result<Vec<Array>> {
        let stream = Stream::thread_local_or_default();
        Vec::<Array>::try_from_op(|res| unsafe {
            if axis == 0 {
                mlx_sys::mlx_unstack(res, self.as_ptr(), stream.as_ref().as_ptr())
            } else {
                mlx_sys::mlx_unstack_axis(res, self.as_ptr(), axis, stream.as_ref().as_ptr())
            }
        })
    }

    /// See [`expand_dims()`].
    pub fn expand_dims(&self, axis: i32) -> Result<Array> {
        expand_dims(self, axis)
    }

    /// Compatibility shim for [`expand_dims`].
    #[deprecated(
        since = "0.26.0",
        note = "use `with_stream` or `with_device` around `expand_dims`"
    )]
    pub fn expand_dims_device(&self, axis: i32, stream: impl AsRef<Stream>) -> Result<Array> {
        crate::with_stream(stream.as_ref(), || self.expand_dims(axis))
    }

    /// See [`expand_dims_axes()`].
    pub fn expand_dims_axes(&self, axes: &[i32]) -> Result<Array> {
        expand_dims_axes(self, axes)
    }

    /// Compatibility shim for [`expand_dims_axes`].
    #[deprecated(
        since = "0.26.0",
        note = "use `with_stream` or `with_device` around `expand_dims_axes`"
    )]
    pub fn expand_dims_axes_device(
        &self,
        axes: &[i32],
        stream: impl AsRef<Stream>,
    ) -> Result<Array> {
        crate::with_stream(stream.as_ref(), || self.expand_dims_axes(axes))
    }

    /// See [`flatten`].
    pub fn flatten(
        &self,
        start_axis: impl Into<Option<i32>>,
        end_axis: impl Into<Option<i32>>,
    ) -> Result<Array> {
        flatten(self, start_axis, end_axis)
    }

    /// Compatibility shim for [`flatten`].
    #[deprecated(
        since = "0.26.0",
        note = "use `with_stream` or `with_device` around `flatten`"
    )]
    pub fn flatten_device(
        &self,
        start_axis: impl Into<Option<i32>>,
        end_axis: impl Into<Option<i32>>,
        stream: impl AsRef<Stream>,
    ) -> Result<Array> {
        crate::with_stream(stream.as_ref(), || self.flatten(start_axis, end_axis))
    }

    /// See [`reshape`].
    pub fn reshape(&self, shape: &[i32]) -> Result<Array> {
        reshape(self, shape)
    }

    /// Compatibility shim for [`reshape`].
    #[deprecated(
        since = "0.26.0",
        note = "use `with_stream` or `with_device` around `reshape`"
    )]
    pub fn reshape_device(&self, shape: &[i32], stream: impl AsRef<Stream>) -> Result<Array> {
        crate::with_stream(stream.as_ref(), || self.reshape(shape))
    }

    /// See [`squeeze_axes()`].
    pub fn squeeze_axes(&self, axes: &[i32]) -> Result<Array> {
        squeeze_axes(self, axes)
    }

    /// Compatibility shim for [`squeeze_axes`].
    #[deprecated(
        since = "0.26.0",
        note = "use `with_stream` or `with_device` around `squeeze_axes`"
    )]
    pub fn squeeze_axes_device(&self, axes: &[i32], stream: impl AsRef<Stream>) -> Result<Array> {
        crate::with_stream(stream.as_ref(), || self.squeeze_axes(axes))
    }

    /// See [`squeeze()`].
    pub fn squeeze(&self) -> Result<Array> {
        squeeze(self)
    }

    /// Compatibility shim for [`squeeze`].
    #[deprecated(
        since = "0.26.0",
        note = "use `with_stream` or `with_device` around `squeeze`"
    )]
    pub fn squeeze_device(&self, stream: impl AsRef<Stream>) -> Result<Array> {
        crate::with_stream(stream.as_ref(), || self.squeeze())
    }

    /// See [`as_strided`]
    pub fn as_strided<'a>(
        &'a self,
        shape: impl IntoOption<&'a [i32]>,
        strides: impl IntoOption<&'a [i64]>,
        offset: impl Into<Option<usize>>,
    ) -> Result<Array> {
        as_strided(self, shape, strides, offset)
    }

    /// Compatibility shim for [`as_strided`].
    #[deprecated(
        since = "0.26.0",
        note = "use `with_stream` or `with_device` around `as_strided`"
    )]
    pub fn as_strided_device<'a>(
        &'a self,
        shape: impl IntoOption<&'a [i32]>,
        strides: impl IntoOption<&'a [i64]>,
        offset: impl Into<Option<usize>>,
        stream: impl AsRef<Stream>,
    ) -> Result<Array> {
        crate::with_stream(stream.as_ref(), || self.as_strided(shape, strides, offset))
    }

    /// See [`at_least_1d`]
    pub fn at_least_1d(&self) -> Result<Array> {
        at_least_1d(self)
    }

    /// Compatibility shim for [`at_least_1d`].
    #[deprecated(
        since = "0.26.0",
        note = "use `with_stream` or `with_device` around `at_least_1d`"
    )]
    pub fn at_least_1d_device(&self, stream: impl AsRef<Stream>) -> Result<Array> {
        crate::with_stream(stream.as_ref(), || self.at_least_1d())
    }

    /// See [`at_least_2d`]
    pub fn at_least_2d(&self) -> Result<Array> {
        at_least_2d(self)
    }

    /// Compatibility shim for [`at_least_2d`].
    #[deprecated(
        since = "0.26.0",
        note = "use `with_stream` or `with_device` around `at_least_2d`"
    )]
    pub fn at_least_2d_device(&self, stream: impl AsRef<Stream>) -> Result<Array> {
        crate::with_stream(stream.as_ref(), || self.at_least_2d())
    }

    /// See [`at_least_3d`]
    pub fn at_least_3d(&self) -> Result<Array> {
        at_least_3d(self)
    }

    /// Compatibility shim for [`at_least_3d`].
    #[deprecated(
        since = "0.26.0",
        note = "use `with_stream` or `with_device` around `at_least_3d`"
    )]
    pub fn at_least_3d_device(&self, stream: impl AsRef<Stream>) -> Result<Array> {
        crate::with_stream(stream.as_ref(), || self.at_least_3d())
    }

    /// See [`move_axis`]
    pub fn move_axis(&self, src: i32, dst: i32) -> Result<Array> {
        move_axis(self, src, dst)
    }

    /// Compatibility shim for [`move_axis`].
    #[deprecated(
        since = "0.26.0",
        note = "use `with_stream` or `with_device` around `move_axis`"
    )]
    pub fn move_axis_device(
        &self,
        src: i32,
        dst: i32,
        stream: impl AsRef<Stream>,
    ) -> Result<Array> {
        crate::with_stream(stream.as_ref(), || self.move_axis(src, dst))
    }

    /// See [`split_at_indices`].
    pub fn split_at_indices(
        &self,
        indices: &[i32],
        axis: impl Into<Option<i32>>,
    ) -> Result<Vec<Array>> {
        split_at_indices(self, indices, axis)
    }

    /// Compatibility alias for [`Array::split_at_indices`].
    #[deprecated(since = "0.26.0", note = "renamed to `split_at_indices`")]
    pub fn split_axis(&self, indices: &[i32], axis: impl Into<Option<i32>>) -> Result<Vec<Array>> {
        self.split_at_indices(indices, axis)
    }

    /// Compatibility shim for [`split_axis`].
    #[deprecated(
        since = "0.26.0",
        note = "use `with_stream` or `with_device` around `split_at_indices`"
    )]
    pub fn split_axis_device(
        &self,
        indices: &[i32],
        axis: impl Into<Option<i32>>,
        stream: impl AsRef<Stream>,
    ) -> Result<Vec<Array>> {
        crate::with_stream(stream.as_ref(), || self.split_at_indices(indices, axis))
    }

    /// See [`split_equal`].
    pub fn split_equal(&self, num_parts: i32, axis: impl Into<Option<i32>>) -> Result<Vec<Array>> {
        split_equal(self, num_parts, axis)
    }

    /// Compatibility alias for [`Array::split_equal`].
    #[deprecated(since = "0.26.0", note = "renamed to `split_equal`")]
    pub fn split(&self, num_parts: i32, axis: impl Into<Option<i32>>) -> Result<Vec<Array>> {
        self.split_equal(num_parts, axis)
    }

    /// Compatibility shim for [`split`].
    #[deprecated(
        since = "0.26.0",
        note = "use `with_stream` or `with_device` around `split_equal`"
    )]
    pub fn split_device(
        &self,
        num_parts: i32,
        axis: impl Into<Option<i32>>,
        stream: impl AsRef<Stream>,
    ) -> Result<Vec<Array>> {
        crate::with_stream(stream.as_ref(), || self.split_equal(num_parts, axis))
    }

    /// See [`swap_axes`]
    pub fn swap_axes(&self, axis1: i32, axis2: i32) -> Result<Array> {
        swap_axes(self, axis1, axis2)
    }

    /// Compatibility shim for [`swap_axes`].
    #[deprecated(
        since = "0.26.0",
        note = "use `with_stream` or `with_device` around `swap_axes`"
    )]
    pub fn swap_axes_device(
        &self,
        axis1: i32,
        axis2: i32,
        stream: impl AsRef<Stream>,
    ) -> Result<Array> {
        crate::with_stream(stream.as_ref(), || self.swap_axes(axis1, axis2))
    }

    /// See [`transpose_axes`]
    pub fn transpose_axes(&self, axes: &[i32]) -> Result<Array> {
        transpose_axes(self, axes)
    }

    /// Compatibility shim for [`transpose_axes`].
    #[deprecated(
        since = "0.26.0",
        note = "use `with_stream` or `with_device` around `transpose_axes`"
    )]
    pub fn transpose_axes_device(&self, axes: &[i32], stream: impl AsRef<Stream>) -> Result<Array> {
        crate::with_stream(stream.as_ref(), || self.transpose_axes(axes))
    }

    /// See [`transpose`]
    pub fn transpose(&self) -> Result<Array> {
        transpose(self)
    }

    /// Compatibility shim for [`transpose`].
    #[deprecated(
        since = "0.26.0",
        note = "use `with_stream` or `with_device` around `transpose`"
    )]
    pub fn transpose_device(&self, stream: impl AsRef<Stream>) -> Result<Array> {
        crate::with_stream(stream.as_ref(), || self.transpose())
    }

    /// [`transpose_axes`] and unwrap the result.
    pub fn t(&self) -> Array {
        self.transpose().unwrap()
    }
}
fn resolve_strides(
    shape: &[i32],
    strides: Option<&[i64]>,
) -> SmallVec<[i64; DEFAULT_STACK_VEC_LEN]> {
    match strides {
        Some(strides) => SmallVec::from_slice(strides),
        None => {
            let result = shape
                .iter()
                .rev()
                .scan(1, |acc, &dim| {
                    let result = *acc;
                    *acc *= dim as i64;
                    Some(result)
                })
                .collect::<SmallVec<[i64; DEFAULT_STACK_VEC_LEN]>>();
            result.into_iter().rev().collect()
        }
    }
}

/// Broadcast a vector of arrays against one another. Returns an error if the shapes are
/// broadcastable.
///
/// # Params
///
/// - `arrays`: The arrays to broadcast.
pub fn broadcast_arrays(arrays: &[impl AsRef<Array>]) -> Result<Vec<Array>> {
    let stream = Stream::thread_local_or_default();
    let c_vec = VectorArray::try_from_iter(arrays.iter())?;
    Vec::<Array>::try_from_op(|res| unsafe {
        mlx_sys::mlx_broadcast_arrays(res, c_vec.as_ptr(), stream.as_ref().as_ptr())
    })
}

/// Compatibility shim for [`broadcast_arrays`].
#[generate_macro(customize(forwarding_shim = true))]
#[deprecated(
    since = "0.26.0",
    note = "use `with_stream` or `with_device` around `broadcast_arrays`"
)]
pub fn broadcast_arrays_device(
    arrays: &[impl AsRef<Array>],
    #[optional] stream: impl AsRef<Stream>,
) -> Result<Vec<Array>> {
    crate::with_stream(stream.as_ref(), || broadcast_arrays(arrays))
}

/// Create a view into the array with the given shape and strides.
///
/// # Example
///
/// ```rust
/// use mlx_rs::{Array, ops::*};
///
/// let x = Array::from_iter(0..10, &[10]);
/// let y = as_strided(&x, &[3, 3], &[1, 1], 0);
/// ```
pub fn as_strided<'a>(
    a: impl AsRef<Array>,
    shape: impl IntoOption<&'a [i32]>,
    strides: impl IntoOption<&'a [i64]>,
    offset: impl Into<Option<usize>>,
) -> Result<Array> {
    let stream = Stream::thread_local_or_default();
    let a = a.as_ref();
    let shape = shape.into_option().unwrap_or(a.shape());
    let resolved_strides = resolve_strides(shape, strides.into_option());
    let offset = offset.into().unwrap_or(0);

    Array::try_from_op(|res| unsafe {
        mlx_sys::mlx_as_strided(
            res,
            a.as_ptr(),
            shape.as_ptr(),
            shape.len(),
            resolved_strides.as_ptr(),
            resolved_strides.len(),
            offset,
            stream.as_ref().as_ptr(),
        )
    })
}

/// Compatibility shim for [`as_strided`].
#[generate_macro(customize(forwarding_shim = true))]
#[deprecated(
    since = "0.26.0",
    note = "use `with_stream` or `with_device` around `as_strided`"
)]
pub fn as_strided_device<'a>(
    a: impl AsRef<Array>,
    #[optional] shape: impl IntoOption<&'a [i32]>,
    #[optional] strides: impl IntoOption<&'a [i64]>,
    #[optional] offset: impl Into<Option<usize>>,
    #[optional] stream: impl AsRef<Stream>,
) -> Result<Array> {
    crate::with_stream(stream.as_ref(), || as_strided(a, shape, strides, offset))
}

/// Broadcast an array to the given shape. Returns an error if the shapes are not broadcastable.
///
/// # Params
///
/// - `a`: The input array.
/// - `shape`: The shape to broadcast to.
///
/// # Example
///
/// ```rust
/// use mlx_rs::{Array, ops::*};
///
/// let x = Array::from_f32(2.3);
/// let result = broadcast_to(&x, &[1, 1]);
/// ```
pub fn broadcast_to(a: impl AsRef<Array>, shape: &[i32]) -> Result<Array> {
    let stream = Stream::thread_local_or_default();
    Array::try_from_op(|res| unsafe {
        mlx_sys::mlx_broadcast_to(
            res,
            a.as_ref().as_ptr(),
            shape.as_ptr(),
            shape.len(),
            stream.as_ref().as_ptr(),
        )
    })
}

/// Compatibility shim for [`broadcast_to`].
#[generate_macro(customize(forwarding_shim = true))]
#[deprecated(
    since = "0.26.0",
    note = "use `with_stream` or `with_device` around `broadcast_to`"
)]
pub fn broadcast_to_device(
    a: impl AsRef<Array>,
    shape: &[i32],
    #[optional] stream: impl AsRef<Stream>,
) -> Result<Array> {
    crate::with_stream(stream.as_ref(), || broadcast_to(a, shape))
}

/// Concatenate the arrays along the given axis. Returns an error if the shapes are invalid.
///
/// # Params
///
/// - `arrays`: The arrays to concatenate.
/// - `axis`: The axis to concatenate along.
///
/// # Example
///
/// ```rust
/// use mlx_rs::{Array, ops::*};
///
/// let x = Array::from_iter(0..4, &[2, 2]);
/// let y = Array::from_iter(4..8, &[2, 2]);
/// let result = concatenate(&[x, y], 0);
/// ```
pub fn concatenate(arrays: &[impl AsRef<Array>], axis: i32) -> Result<Array> {
    let stream = Stream::thread_local_or_default();
    let c_arrays = VectorArray::try_from_iter(arrays.iter())?;
    Array::try_from_op(|res| unsafe {
        mlx_sys::mlx_concatenate_axis(res, c_arrays.as_ptr(), axis, stream.as_ref().as_ptr())
    })
}

/// Compatibility alias for [`concatenate`].
#[deprecated(since = "0.26.0", note = "renamed to `concatenate`")]
pub fn concatenate_axis(arrays: &[impl AsRef<Array>], axis: i32) -> Result<Array> {
    concatenate(arrays, axis)
}

/// Compatibility shim for [`concatenate`].
#[generate_macro(customize(forwarding_shim = true))]
#[deprecated(
    since = "0.26.0",
    note = "use `with_stream` or `with_device` around `concatenate`"
)]
pub fn concatenate_axis_device(
    arrays: &[impl AsRef<Array>],
    axis: i32,
    #[optional] stream: impl AsRef<Stream>,
) -> Result<Array> {
    crate::with_stream(stream.as_ref(), || concatenate(arrays, axis))
}

/// Flatten the arrays and concatenate them. Use [`concatenate`] to concatenate along an axis.
pub fn concatenate_flat(arrays: &[impl AsRef<Array>]) -> Result<Array> {
    let stream = Stream::thread_local_or_default();
    let c_arrays = VectorArray::try_from_iter(arrays.iter())?;
    Array::try_from_op(|res| unsafe {
        mlx_sys::mlx_concatenate(res, c_arrays.as_ptr(), stream.as_ref().as_ptr())
    })
}

/// Compatibility shim preserving the old flattening behavior of `concatenate`.
#[generate_macro(customize(forwarding_shim = true))]
#[deprecated(
    since = "0.26.0",
    note = "the old `concatenate` flattened inputs; use `concatenate_flat`"
)]
pub fn concatenate_device(
    arrays: &[impl AsRef<Array>],
    #[optional] stream: impl AsRef<Stream>,
) -> Result<Array> {
    crate::with_stream(stream.as_ref(), || concatenate_flat(arrays))
}

/// Add a size one dimension at the given axis, returns an error if the axes are invalid.
///
/// # Params
///
/// - `a`: The input array.
/// - `axes`: The index of the inserted dimensions.
///
/// # Example
///
/// ```rust
/// use mlx_rs::{Array, ops::*};
///
/// let x = Array::zeros::<i32>(&[2, 2]).unwrap();
/// let result = expand_dims_axes(&x, &[0]);
/// ```
pub fn expand_dims_axes(a: impl AsRef<Array>, axes: &[i32]) -> Result<Array> {
    let stream = Stream::thread_local_or_default();
    Array::try_from_op(|res| unsafe {
        mlx_sys::mlx_expand_dims_axes(
            res,
            a.as_ref().as_ptr(),
            axes.as_ptr(),
            axes.len(),
            stream.as_ref().as_ptr(),
        )
    })
}

/// Compatibility shim for [`expand_dims_axes`].
#[generate_macro(customize(forwarding_shim = true))]
#[deprecated(
    since = "0.26.0",
    note = "use `with_stream` or `with_device` around `expand_dims_axes`"
)]
pub fn expand_dims_axes_device(
    a: impl AsRef<Array>,
    axes: &[i32],
    #[optional] stream: impl AsRef<Stream>,
) -> Result<Array> {
    crate::with_stream(stream.as_ref(), || expand_dims_axes(a, axes))
}

/// Similar to [`expand_dims_axes`], but only takes a single axis.
pub fn expand_dims(a: impl AsRef<Array>, axis: i32) -> Result<Array> {
    let stream = Stream::thread_local_or_default();
    Array::try_from_op(|res| unsafe {
        mlx_sys::mlx_expand_dims(res, a.as_ref().as_ptr(), axis, stream.as_ref().as_ptr())
    })
}

/// Compatibility shim for [`expand_dims`].
#[generate_macro(customize(forwarding_shim = true))]
#[deprecated(
    since = "0.26.0",
    note = "use `with_stream` or `with_device` around `expand_dims`"
)]
pub fn expand_dims_device(
    a: impl AsRef<Array>,
    axis: i32,
    #[optional] stream: impl AsRef<Stream>,
) -> Result<Array> {
    crate::with_stream(stream.as_ref(), || expand_dims(a, axis))
}

/// Flatten an array. Returns an error if the axes are invalid.
///
/// The axes flattened will be between `start_axis` and `end_axis`, inclusive. Negative axes are
/// supported. After converting negative axis to positive, axes outside the valid range will be
/// clamped to a valid value, `start_axis` to `0` and `end_axis` to `ndim - 1`.
///
/// # Params
///
/// - `a`: The input array.
/// - `start_axis`: The first axis to flatten. Default is `0` if not provided.
/// - `end_axis`: The last axis to flatten. Default is `-1` if not provided.
///
/// # Example
///
/// ```rust
/// use mlx_rs::{Array, ops::*};
///
/// let x = Array::zeros::<i32>(&[2, 2, 2]).unwrap();
/// let y = flatten(&x, None, None);
/// ```
pub fn flatten(
    a: impl AsRef<Array>,
    start_axis: impl Into<Option<i32>>,
    end_axis: impl Into<Option<i32>>,
) -> Result<Array> {
    let stream = Stream::thread_local_or_default();
    let start_axis = start_axis.into().unwrap_or(0);
    let end_axis = end_axis.into().unwrap_or(-1);

    Array::try_from_op(|res| unsafe {
        mlx_sys::mlx_flatten(
            res,
            a.as_ref().as_ptr(),
            start_axis,
            end_axis,
            stream.as_ref().as_ptr(),
        )
    })
}

/// Compatibility shim for [`flatten`].
#[generate_macro(customize(forwarding_shim = true))]
#[deprecated(
    since = "0.26.0",
    note = "use `with_stream` or `with_device` around `flatten`"
)]
pub fn flatten_device(
    a: impl AsRef<Array>,
    #[optional] start_axis: impl Into<Option<i32>>,
    #[optional] end_axis: impl Into<Option<i32>>,
    #[optional] stream: impl AsRef<Stream>,
) -> Result<Array> {
    crate::with_stream(stream.as_ref(), || flatten(a, start_axis, end_axis))
}

/// Unflatten an axis of an array to a shape.
///
/// # Params
///
/// - `a`: input array
/// - `axis`: axis to unflatten
/// - `shape`: shape to unflatten into
pub fn unflatten(a: impl AsRef<Array>, axis: i32, shape: &[i32]) -> Result<Array> {
    let stream = Stream::thread_local_or_default();
    Array::try_from_op(|res| unsafe {
        mlx_sys::mlx_unflatten(
            res,
            a.as_ref().as_ptr(),
            axis,
            shape.as_ptr(),
            shape.len(),
            stream.as_ref().as_ptr(),
        )
    })
}

/// Compatibility shim for [`unflatten`].
#[generate_macro(customize(forwarding_shim = true))]
#[deprecated(
    since = "0.26.0",
    note = "use `with_stream` or `with_device` around `unflatten`"
)]
pub fn unflatten_device(
    a: impl AsRef<Array>,
    axis: i32,
    shape: &[i32],
    #[optional] stream: impl AsRef<Stream>,
) -> Result<Array> {
    crate::with_stream(stream.as_ref(), || unflatten(a, axis, shape))
}

/// Reshape an array while preserving the size. Returns an error if the new shape is invalid.
///
/// # Params
///
/// - `a`: The input array.
/// - `shape`: New shape.
///
/// # Example
///
/// ```rust
/// use mlx_rs::{Array, ops::*};
///
/// let x = Array::zeros::<i32>(&[2, 2]).unwrap();
/// let result = reshape(&x, &[4]);
/// ```
pub fn reshape(a: impl AsRef<Array>, shape: &[i32]) -> Result<Array> {
    let stream = Stream::thread_local_or_default();
    Array::try_from_op(|res| unsafe {
        mlx_sys::mlx_reshape(
            res,
            a.as_ref().as_ptr(),
            shape.as_ptr(),
            shape.len(),
            stream.as_ref().as_ptr(),
        )
    })
}

/// Compatibility shim for [`reshape`].
#[generate_macro(customize(forwarding_shim = true))]
#[deprecated(
    since = "0.26.0",
    note = "use `with_stream` or `with_device` around `reshape`"
)]
pub fn reshape_device(
    a: impl AsRef<Array>,
    shape: &[i32],
    #[optional] stream: impl AsRef<Stream>,
) -> Result<Array> {
    crate::with_stream(stream.as_ref(), || reshape(a, shape))
}

/// Remove length one axes from an array. Returns an error if the axes are invalid.
///
/// # Params
///
/// - `a`: The input array.
/// - `axes`: Axes to remove. If `None`, all length one axes will be removed.
///
/// # Example
///
/// ```rust
/// use mlx_rs::{Array, ops::*};
///
/// let x = Array::zeros::<i32>(&[1, 2, 1, 3]).unwrap();
/// let result = squeeze(&x);
/// ```
pub fn squeeze_axes(a: impl AsRef<Array>, axes: &[i32]) -> Result<Array> {
    let stream = Stream::thread_local_or_default();
    let a = a.as_ref();
    Array::try_from_op(|res| unsafe {
        mlx_sys::mlx_squeeze_axes(
            res,
            a.as_ptr(),
            axes.as_ptr(),
            axes.len(),
            stream.as_ref().as_ptr(),
        )
    })
}

/// Compatibility shim for [`squeeze_axes`].
#[generate_macro(customize(forwarding_shim = true))]
#[deprecated(
    since = "0.26.0",
    note = "use `with_stream` or `with_device` around `squeeze_axes`"
)]
pub fn squeeze_axes_device(
    a: impl AsRef<Array>,
    axes: &[i32],
    #[optional] stream: impl AsRef<Stream>,
) -> Result<Array> {
    crate::with_stream(stream.as_ref(), || squeeze_axes(a, axes))
}

/// Similar to [`squeeze_axes`], but removes all length one axes.
pub fn squeeze(a: impl AsRef<Array>) -> Result<Array> {
    let stream = Stream::thread_local_or_default();
    let a = a.as_ref();
    Array::try_from_op(|res| unsafe {
        mlx_sys::mlx_squeeze(res, a.as_ptr(), stream.as_ref().as_ptr())
    })
}

/// Compatibility shim for [`squeeze`].
#[generate_macro(customize(forwarding_shim = true))]
#[deprecated(
    since = "0.26.0",
    note = "use `with_stream` or `with_device` around `squeeze`"
)]
pub fn squeeze_device(
    a: impl AsRef<Array>,
    #[optional] stream: impl AsRef<Stream>,
) -> Result<Array> {
    crate::with_stream(stream.as_ref(), || squeeze(a))
}

/// Convert array to have at least one dimension.
///
/// # Params
///
/// - `a`: The input array.
///
/// # Example
///
/// ```rust
/// use mlx_rs::{Array, ops::*};
///
/// let x = Array::from_int(1);
/// let out = at_least_1d(&x);
/// ```
pub fn at_least_1d(a: impl AsRef<Array>) -> Result<Array> {
    let stream = Stream::thread_local_or_default();
    Array::try_from_op(|res| unsafe {
        mlx_sys::mlx_atleast_1d(res, a.as_ref().as_ptr(), stream.as_ref().as_ptr())
    })
}

/// Compatibility shim for [`at_least_1d`].
#[generate_macro(customize(forwarding_shim = true))]
#[deprecated(
    since = "0.26.0",
    note = "use `with_stream` or `with_device` around `at_least_1d`"
)]
pub fn at_least_1d_device(
    a: impl AsRef<Array>,
    #[optional] stream: impl AsRef<Stream>,
) -> Result<Array> {
    crate::with_stream(stream.as_ref(), || at_least_1d(a))
}

/// Convert array to have at least two dimensions.
///
/// # Params
///
/// - `a`: The input array.
///
/// # Example
///
/// ```rust
/// use mlx_rs::{Array, ops::*};
///
/// let x = Array::from_int(1);
/// let out = at_least_2d(&x);
/// ```
pub fn at_least_2d(a: impl AsRef<Array>) -> Result<Array> {
    let stream = Stream::thread_local_or_default();
    Array::try_from_op(|res| unsafe {
        mlx_sys::mlx_atleast_2d(res, a.as_ref().as_ptr(), stream.as_ref().as_ptr())
    })
}

/// Compatibility shim for [`at_least_2d`].
#[generate_macro(customize(forwarding_shim = true))]
#[deprecated(
    since = "0.26.0",
    note = "use `with_stream` or `with_device` around `at_least_2d`"
)]
pub fn at_least_2d_device(
    a: impl AsRef<Array>,
    #[optional] stream: impl AsRef<Stream>,
) -> Result<Array> {
    crate::with_stream(stream.as_ref(), || at_least_2d(a))
}

/// Convert array to have at least three dimensions.
///
/// # Params
///
/// - `a`: The input array.
///
/// # Example
///
/// ```rust
/// use mlx_rs::{Array, ops::*};
///
/// let x = Array::from_int(1);
/// let out = at_least_3d(&x);
/// ```
pub fn at_least_3d(a: impl AsRef<Array>) -> Result<Array> {
    let stream = Stream::thread_local_or_default();
    Array::try_from_op(|res| unsafe {
        mlx_sys::mlx_atleast_3d(res, a.as_ref().as_ptr(), stream.as_ref().as_ptr())
    })
}

/// Compatibility shim for [`at_least_3d`].
#[generate_macro(customize(forwarding_shim = true))]
#[deprecated(
    since = "0.26.0",
    note = "use `with_stream` or `with_device` around `at_least_3d`"
)]
pub fn at_least_3d_device(
    a: impl AsRef<Array>,
    #[optional] stream: impl AsRef<Stream>,
) -> Result<Array> {
    crate::with_stream(stream.as_ref(), || at_least_3d(a))
}

/// Move an axis to a new position. Returns an error if the axes are invalid.
///
/// # Params
///
/// - `a`: The input array.
/// - `src`: Specifies the source axis.
/// - `dst`: Specifies the destination axis.
///
/// # Example
///
/// ```rust
/// use mlx_rs::{Array, ops::*};
///
/// let a = Array::zeros::<i32>(&[2, 3, 4]).unwrap();
/// let result = move_axis(&a, 0, 2);
/// ```
pub fn move_axis(a: impl AsRef<Array>, src: i32, dst: i32) -> Result<Array> {
    let stream = Stream::thread_local_or_default();
    Array::try_from_op(|res| unsafe {
        mlx_sys::mlx_moveaxis(res, a.as_ref().as_ptr(), src, dst, stream.as_ref().as_ptr())
    })
}

/// Compatibility shim for [`move_axis`].
#[generate_macro(customize(forwarding_shim = true))]
#[deprecated(
    since = "0.26.0",
    note = "use `with_stream` or `with_device` around `move_axis`"
)]
pub fn move_axis_device(
    a: impl AsRef<Array>,
    src: i32,
    dst: i32,
    #[optional] stream: impl AsRef<Stream>,
) -> Result<Array> {
    crate::with_stream(stream.as_ref(), || move_axis(a, src, dst))
}

/// Split an array along a given axis. Returns an error if the indices are invalid.
///
/// # Params
///
/// - `a`: The input array.
/// - `indices`: The indices to split at.
/// - `axis`: The axis to split along. Default is `0` if not provided.
///
/// # Example
///
/// ```rust
/// use mlx_rs::{Array, ops::*};
///
/// let a = Array::from_iter(0..10, &[10]);
/// let result = split_at_indices(&a, &[3, 7], 0);
/// ```
pub fn split_at_indices(
    a: impl AsRef<Array>,
    indices: &[i32],
    axis: impl Into<Option<i32>>,
) -> Result<Vec<Array>> {
    let stream = Stream::thread_local_or_default();
    let axis = axis.into().unwrap_or(0);
    Vec::<Array>::try_from_op(|res| unsafe {
        mlx_sys::mlx_split_sections(
            res,
            a.as_ref().as_ptr(),
            indices.as_ptr(),
            indices.len(),
            axis,
            stream.as_ref().as_ptr(),
        )
    })
}

/// Compatibility alias for [`split_at_indices`].
#[deprecated(since = "0.26.0", note = "renamed to `split_at_indices`")]
pub fn split_sections(
    a: impl AsRef<Array>,
    indices: &[i32],
    axis: impl Into<Option<i32>>,
) -> Result<Vec<Array>> {
    split_at_indices(a, indices, axis)
}

/// Compatibility shim for [`split_at_indices`].
#[generate_macro(customize(forwarding_shim = true))]
#[deprecated(
    since = "0.26.0",
    note = "use `with_stream` or `with_device` around `split_at_indices`"
)]
pub fn split_sections_device(
    a: impl AsRef<Array>,
    indices: &[i32],
    #[optional] axis: impl Into<Option<i32>>,
    #[optional] stream: impl AsRef<Stream>,
) -> Result<Vec<Array>> {
    crate::with_stream(stream.as_ref(), || split_at_indices(a, indices, axis))
}

/// Split an array into equal parts along a given axis. Returns an error if the array cannot be
/// split into equal parts.
///
/// # Params
///
/// - `a`: The input array.
/// - `num_parts`: The number of parts to split into.
/// - `axis`: The axis to split along. Default is `0` if not provided.
///
/// # Example
///
/// ```rust
/// use mlx_rs::{Array, ops::*};
///
/// let a = Array::from_iter(0..10, &[10]);
/// let result = split_equal(&a, 2, 0);
/// ```
pub fn split_equal(
    a: impl AsRef<Array>,
    num_parts: i32,
    axis: impl Into<Option<i32>>,
) -> Result<Vec<Array>> {
    let stream = Stream::thread_local_or_default();
    let axis = axis.into().unwrap_or(0);
    Vec::<Array>::try_from_op(|res| unsafe {
        mlx_sys::mlx_split(
            res,
            a.as_ref().as_ptr(),
            num_parts,
            axis,
            stream.as_ref().as_ptr(),
        )
    })
}

/// Compatibility alias for [`split_equal`].
#[deprecated(since = "0.26.0", note = "renamed to `split_equal`")]
pub fn split(
    a: impl AsRef<Array>,
    num_parts: i32,
    axis: impl Into<Option<i32>>,
) -> Result<Vec<Array>> {
    split_equal(a, num_parts, axis)
}

/// Compatibility shim for [`split_equal`].
#[generate_macro(customize(forwarding_shim = true))]
#[deprecated(
    since = "0.26.0",
    note = "use `with_stream` or `with_device` around `split_equal`"
)]
pub fn split_device(
    a: impl AsRef<Array>,
    num_parts: i32,
    #[optional] axis: impl Into<Option<i32>>,
    #[optional] stream: impl AsRef<Stream>,
) -> Result<Vec<Array>> {
    crate::with_stream(stream.as_ref(), || split_equal(a, num_parts, axis))
}

/// Number of padding values to add to the edges of each axis.
#[derive(Debug)]
pub enum PadWidth<'a> {
    /// (before, after) values for all axes.
    Same((i32, i32)),

    /// List of (before, after) values for each axis.
    Widths(&'a [(i32, i32)]),
}

impl From<i32> for PadWidth<'_> {
    fn from(width: i32) -> Self {
        PadWidth::Same((width, width))
    }
}

impl From<(i32, i32)> for PadWidth<'_> {
    fn from(width: (i32, i32)) -> Self {
        PadWidth::Same(width)
    }
}

impl<'a> From<&'a [(i32, i32)]> for PadWidth<'a> {
    fn from(widths: &'a [(i32, i32)]) -> Self {
        PadWidth::Widths(widths)
    }
}

impl<'a, const N: usize> From<&'a [(i32, i32); N]> for PadWidth<'a> {
    fn from(widths: &'a [(i32, i32); N]) -> Self {
        PadWidth::Widths(widths)
    }
}

impl PadWidth<'_> {
    fn low_pads(&self, ndim: usize) -> SmallVec<[i32; DEFAULT_STACK_VEC_LEN]> {
        match self {
            PadWidth::Same((low, _high)) => (0..ndim).map(|_| *low).collect(),
            PadWidth::Widths(widths) => widths.iter().map(|(low, _high)| *low).collect(),
        }
    }
    fn high_pads(&self, ndim: usize) -> SmallVec<[i32; DEFAULT_STACK_VEC_LEN]> {
        match self {
            PadWidth::Same((_low, high)) => (0..ndim).map(|_| *high).collect(),
            PadWidth::Widths(widths) => widths.iter().map(|(_low, high)| *high).collect(),
        }
    }
}

/// The padding mode.
#[derive(Debug)]
pub enum PadMode {
    /// Pad with a constant value.
    Constant,

    /// Pad with the edge value.
    Edge,
}

impl PadMode {
    unsafe fn as_c_str(&self) -> *const i8 {
        static CONSTANT: &[u8] = b"constant\0";
        static EDGE: &[u8] = b"edge\0";

        match self {
            PadMode::Constant => CONSTANT.as_ptr() as *const _,
            PadMode::Edge => EDGE.as_ptr() as *const _,
        }
    }
}

/// Pad an array with a constant value. Returns an error if the width is invalid.
///
/// # Params
///
/// - `a`: The input array.
/// - `width`: Number of padded values to add to the edges of each axis:`((before_1, after_1),
///   (before_2, after_2), ..., (before_N, after_N))`. If a single pair of integers is passed then
///   `(before_i, after_i)` are all the same. If a single integer or tuple with a single integer is
///   passed then all axes are extended by the same number on each side.
/// - `value`: The value to pad the array with. Default is `0` if not provided.
/// - `mode`: The padding mode. Default is `PadMode::Constant` if not provided.
///
/// # Example
///
/// ```rust
/// use mlx_rs::{Array, ops::*};
///
/// let a = Array::from_iter(0..4, &[2, 2]);
/// let result = pad(&a, 1, Array::from_int(0), None);
/// ```
pub fn pad<'a>(
    a: impl AsRef<Array>,
    width: impl Into<PadWidth<'a>>,
    value: impl Into<Option<Array>>,
    mode: impl Into<Option<PadMode>>,
) -> Result<Array> {
    let stream = Stream::thread_local_or_default();
    let a = a.as_ref();
    let width = width.into();
    let ndim = a.ndim();
    let axes: SmallVec<[i32; DEFAULT_STACK_VEC_LEN]> = (0..ndim).map(|i| i as i32).collect();
    let low_pads = width.low_pads(ndim);
    let high_pads = width.high_pads(ndim);
    let value = value
        .into()
        .map(Ok)
        .unwrap_or_else(|| Array::from_int(0).as_dtype(a.dtype()))?;
    let mode = mode.into().unwrap_or(PadMode::Constant);

    Array::try_from_op(|res| unsafe {
        mlx_sys::mlx_pad(
            res,
            a.as_ptr(),
            axes.as_ptr(),
            axes.len(),
            low_pads.as_ptr(),
            low_pads.len(),
            high_pads.as_ptr(),
            high_pads.len(),
            value.as_ptr(),
            mode.as_c_str(),
            stream.as_ref().as_ptr(),
        )
    })
}

/// Compatibility shim for [`pad`].
#[generate_macro(customize(forwarding_shim = true))]
#[deprecated(
    since = "0.26.0",
    note = "use `with_stream` or `with_device` around `pad`"
)]
pub fn pad_device<'a>(
    a: impl AsRef<Array>,
    #[optional] width: impl Into<PadWidth<'a>>,
    #[optional] value: impl Into<Option<Array>>,
    #[optional] mode: impl Into<Option<PadMode>>,
    #[optional] stream: impl AsRef<Stream>,
) -> Result<Array> {
    crate::with_stream(stream.as_ref(), || pad(a, width, value, mode))
}

/// Stacks the arrays along a new axis. Returns an error if the arguments are invalid.
///
/// # Params
///
/// - `arrays`: The input arrays.
/// - `axis`: The axis in the result array along which the input arrays are stacked.
///
/// # Example
///
/// ```rust
/// use mlx_rs::{Array, ops::*};
///
/// let a = Array::from_iter(0..4, &[2, 2]);
/// let b = Array::from_iter(4..8, &[2, 2]);
/// let result = stack(&[&a, &b], 0);
/// ```
pub fn stack(arrays: &[impl AsRef<Array>], axis: i32) -> Result<Array> {
    let stream = Stream::thread_local_or_default();
    let c_vec = VectorArray::try_from_iter(arrays.iter())?;
    Array::try_from_op(|res| unsafe {
        mlx_sys::mlx_stack_axis(res, c_vec.as_ptr(), axis, stream.as_ref().as_ptr())
    })
}

/// Compatibility alias for [`stack`].
#[deprecated(since = "0.26.0", note = "renamed to `stack`")]
pub fn stack_axis(arrays: &[impl AsRef<Array>], axis: i32) -> Result<Array> {
    stack(arrays, axis)
}

/// Compatibility shim for [`stack`].
#[generate_macro(customize(forwarding_shim = true))]
#[deprecated(
    since = "0.26.0",
    note = "use `with_stream` or `with_device` around `stack`"
)]
pub fn stack_axis_device(
    arrays: &[impl AsRef<Array>],
    axis: i32,
    #[optional] stream: impl AsRef<Stream>,
) -> Result<Array> {
    crate::with_stream(stream.as_ref(), || stack(arrays, axis))
}

/// Compatibility shim preserving the old axis-zero behavior of `stack`.
#[generate_macro(customize(forwarding_shim = true))]
#[deprecated(
    since = "0.26.0",
    note = "the old `stack` used axis 0; use `stack(arrays, 0)`"
)]
pub fn stack_device(
    arrays: &[impl AsRef<Array>],
    #[optional] stream: impl AsRef<Stream>,
) -> Result<Array> {
    crate::with_stream(stream.as_ref(), || stack(arrays, 0))
}

/// Swap two axes of an array. Returns an error if the axes are invalid.
///
/// # Params
///
/// - `a`: The input array.
/// - `axis1`: The first axis.
/// - `axis2`: The second axis.
///
/// # Example
///
/// ```rust
/// use mlx_rs::{Array, ops::*};
///
/// let a = Array::from_iter(0..6, &[2, 3]);
/// let result = swap_axes(&a, 0, 1);
/// ```
pub fn swap_axes(a: impl AsRef<Array>, axis1: i32, axis2: i32) -> Result<Array> {
    let stream = Stream::thread_local_or_default();
    Array::try_from_op(|res| unsafe {
        mlx_sys::mlx_swapaxes(
            res,
            a.as_ref().as_ptr(),
            axis1,
            axis2,
            stream.as_ref().as_ptr(),
        )
    })
}

/// Compatibility shim for [`swap_axes`].
#[generate_macro(customize(forwarding_shim = true))]
#[deprecated(
    since = "0.26.0",
    note = "use `with_stream` or `with_device` around `swap_axes`"
)]
pub fn swap_axes_device(
    a: impl AsRef<Array>,
    axis1: i32,
    axis2: i32,
    #[optional] stream: impl AsRef<Stream>,
) -> Result<Array> {
    crate::with_stream(stream.as_ref(), || swap_axes(a, axis1, axis2))
}

/// Construct an array by repeating `a` the number of times given by `reps`.
///
/// # Params
///
/// - `a`: The input array.
/// - `reps`: The number of repetitions along each axis.
///
/// # Example
///
/// ```rust
/// use mlx_rs::{Array, ops::*};
///
/// let x = Array::from_slice(&[1, 2, 3], &[3]);
/// let y = tile(&x, &[2]);
/// ```
pub fn tile(a: impl AsRef<Array>, reps: &[i32]) -> Result<Array> {
    let stream = Stream::thread_local_or_default();
    Array::try_from_op(|res| unsafe {
        mlx_sys::mlx_tile(
            res,
            a.as_ref().as_ptr(),
            reps.as_ptr(),
            reps.len(),
            stream.as_ref().as_ptr(),
        )
    })
}

/// Compatibility shim for [`tile`].
#[generate_macro(customize(forwarding_shim = true))]
#[deprecated(
    since = "0.26.0",
    note = "use `with_stream` or `with_device` around `tile`"
)]
pub fn tile_device(
    a: impl AsRef<Array>,
    reps: &[i32],
    #[optional] stream: impl AsRef<Stream>,
) -> Result<Array> {
    crate::with_stream(stream.as_ref(), || tile(a, reps))
}

/// Transpose the dimensions of the array. Returns an error if the axes are invalid.
///
/// # Params
///
/// - `a`: The input array.
/// - `axes`: Specifies the source axis for each axis in the new array. The default is to reverse
///   the axes.
///
/// # Example
///
/// ```rust
/// use mlx_rs::{Array, ops::*};
///
/// let x = Array::from_slice(&[1, 2, 3, 4, 5, 6], &[2, 3]);
/// let y1 = transpose_axes(&x, &[0, 1]).unwrap();
/// let y2 = transpose(&x).unwrap();
/// ```
///
/// # See also
///
/// - [`transpose`]
pub fn transpose_axes(a: impl AsRef<Array>, axes: &[i32]) -> Result<Array> {
    let stream = Stream::thread_local_or_default();
    Array::try_from_op(|res| unsafe {
        mlx_sys::mlx_transpose_axes(
            res,
            a.as_ref().as_ptr(),
            axes.as_ptr(),
            axes.len(),
            stream.as_ref().as_ptr(),
        )
    })
}

/// Compatibility shim for [`transpose_axes`].
#[generate_macro(customize(forwarding_shim = true))]
#[deprecated(
    since = "0.26.0",
    note = "use `with_stream` or `with_device` around `transpose_axes`"
)]
pub fn transpose_axes_device(
    a: impl AsRef<Array>,
    axes: &[i32],
    #[optional] stream: impl AsRef<Stream>,
) -> Result<Array> {
    crate::with_stream(stream.as_ref(), || transpose_axes(a, axes))
}

/// Transpose with all axes reversed
pub fn transpose(a: impl AsRef<Array>) -> Result<Array> {
    let stream = Stream::thread_local_or_default();
    Array::try_from_op(|res| unsafe {
        mlx_sys::mlx_transpose(res, a.as_ref().as_ptr(), stream.as_ref().as_ptr())
    })
}

/// Compatibility shim for [`transpose`].
#[generate_macro(customize(forwarding_shim = true))]
#[deprecated(
    since = "0.26.0",
    note = "use `with_stream` or `with_device` around `transpose`"
)]
pub fn transpose_device(
    a: impl AsRef<Array>,
    #[optional] stream: impl AsRef<Stream>,
) -> Result<Array> {
    crate::with_stream(stream.as_ref(), || transpose(a))
}

// The unit tests below are adapted from
// https://github.com/ml-explore/mlx/blob/main/tests/ops_tests.cpp
#[cfg(test)]
mod tests {
    use crate::{
        array,
        test_utils::{assert_array_eq, tolerances},
        Array, Dtype,
    };

    use super::*;

    #[test]
    fn test_squeeze() {
        let a = Array::zeros::<i32>(&[2, 1, 2, 1, 2, 1]).unwrap();
        assert_eq!(
            squeeze_axes(&a, &[1, 3, 5][..]).unwrap().shape(),
            &[2, 2, 2]
        );
        assert_eq!(
            squeeze_axes(&a, &[-1, -3, -5][..]).unwrap().shape(),
            &[2, 2, 2]
        );
        assert_eq!(
            squeeze_axes(&a, &[1][..]).unwrap().shape(),
            &[2, 2, 1, 2, 1]
        );
        assert_eq!(
            squeeze_axes(&a, &[-1][..]).unwrap().shape(),
            &[2, 1, 2, 1, 2]
        );

        assert!(squeeze_axes(&a, &[0][..]).is_err());
        assert!(squeeze_axes(&a, &[2][..]).is_err());
        assert!(squeeze_axes(&a, &[1, 3, 1][..]).is_err());
        assert!(squeeze_axes(&a, &[1, 3, -3][..]).is_err());
    }

    #[test]
    fn test_expand_dims() {
        let a = Array::zeros::<i32>(&[2, 2]).unwrap();
        assert_eq!(expand_dims_axes(&a, &[0][..]).unwrap().shape(), &[1, 2, 2]);
        assert_eq!(expand_dims_axes(&a, &[-1][..]).unwrap().shape(), &[2, 2, 1]);
        assert_eq!(expand_dims_axes(&a, &[1][..]).unwrap().shape(), &[2, 1, 2]);
        assert_eq!(
            expand_dims_axes(&a, &[0, 1, 2]).unwrap().shape(),
            &[1, 1, 1, 2, 2]
        );
        assert_eq!(
            expand_dims_axes(&a, &[0, 1, 2, 5, 6, 7]).unwrap().shape(),
            &[1, 1, 1, 2, 2, 1, 1, 1]
        );

        assert!(expand_dims_axes(&a, &[3]).is_err());
        assert!(expand_dims_axes(&a, &[0, 1, 0]).is_err());
        assert!(expand_dims_axes(&a, &[0, 1, -4]).is_err());
    }

    #[test]
    fn test_flatten() {
        let x = Array::zeros::<i32>(&[2, 3, 4]).unwrap();
        assert_eq!(flatten(&x, None, None).unwrap().shape(), &[2 * 3 * 4]);

        assert_eq!(flatten(&x, 1, 1).unwrap().shape(), &[2, 3, 4]);
        assert_eq!(flatten(&x, 1, 2).unwrap().shape(), &[2, 3 * 4]);
        assert_eq!(flatten(&x, 1, 3).unwrap().shape(), &[2, 3 * 4]);
        assert_eq!(flatten(&x, 1, -1).unwrap().shape(), &[2, 3 * 4]);
        assert_eq!(flatten(&x, -2, -1).unwrap().shape(), &[2, 3 * 4]);
        assert_eq!(flatten(&x, -3, -1).unwrap().shape(), &[2 * 3 * 4]);
        assert_eq!(flatten(&x, -4, -1).unwrap().shape(), &[2 * 3 * 4]);

        assert!(flatten(&x, 2, 1).is_err());

        assert!(flatten(&x, 5, 6).is_err());

        assert!(flatten(&x, -5, -4).is_err());

        let x = Array::from_int(1);
        assert_eq!(flatten(&x, -3, -1).unwrap().shape(), &[1]);
        assert_eq!(flatten(&x, 0, 0).unwrap().shape(), &[1]);
    }

    #[test]
    fn test_unflatten() {
        let a = array!([1, 2, 3, 4]);
        let b = unflatten(&a, 0, &[2, -1]).unwrap();
        let expected = array!([[1, 2], [3, 4]]);
        assert_array_eq(b, expected, tolerances::EXACT.rtol, tolerances::EXACT.atol);
    }

    #[test]
    fn test_reshape() {
        let x = Array::from_int(1);
        assert!(reshape(&x, &[]).unwrap().shape().is_empty());
        assert!(reshape(&x, &[2]).is_err());
        let y = reshape(&x, &[1, 1, 1]).unwrap();
        assert_eq!(y.shape(), &[1, 1, 1]);
        let y = reshape(&x, &[-1, 1, 1]).unwrap();
        assert_eq!(y.shape(), &[1, 1, 1]);
        let y = reshape(&x, &[1, 1, -1]).unwrap();
        assert_eq!(y.shape(), &[1, 1, 1]);
        assert!(reshape(&x, &[1, -1, -1]).is_err());
        assert!(reshape(&x, &[2, -1]).is_err());

        let x = Array::zeros::<i32>(&[2, 2, 2]).unwrap();
        let y = reshape(&x, &[8]).unwrap();
        assert_eq!(y.shape(), &[8]);
        assert!(reshape(&x, &[7]).is_err());
        let y = reshape(&x, &[-1]).unwrap();
        assert_eq!(y.shape(), &[8]);
        let y = reshape(&x, &[-1, 2]).unwrap();
        assert_eq!(y.shape(), &[4, 2]);
        assert!(reshape(&x, &[-1, 7]).is_err());

        let x = Array::from_slice::<i32>(&[], &[0]);
        let y = reshape(&x, &[0, 0, 0]).unwrap();
        assert_eq!(y.shape(), &[0, 0, 0]);
        y.eval().unwrap();
        assert_eq!(y.size(), 0);
        assert!(reshape(&x, &[]).is_err());
        assert!(reshape(&x, &[1]).is_err());
        let y = reshape(&x, &[1, 5, 0]).unwrap();
        assert_eq!(y.shape(), &[1, 5, 0]);
    }

    #[test]
    fn test_as_strided() {
        let x = Array::from_iter(0..10, &[10]);
        let y = as_strided(&x, &[3, 3][..], &[1, 1][..], 0).unwrap();
        let expected = Array::from_slice(&[0, 1, 2, 1, 2, 3, 2, 3, 4], &[3, 3]);
        assert_array_eq(y, expected, tolerances::EXACT.rtol, tolerances::EXACT.atol);

        let y = as_strided(&x, &[3, 3][..], &[0, 3][..], 0).unwrap();
        let expected = Array::from_slice(&[0, 3, 6, 0, 3, 6, 0, 3, 6], &[3, 3]);
        assert_array_eq(y, expected, tolerances::EXACT.rtol, tolerances::EXACT.atol);

        let x = x.reshape(&[2, 5]).unwrap();
        let x = x.transpose_axes(&[1, 0][..]).unwrap();
        let y = as_strided(&x, &[3, 3][..], &[2, 1][..], 1).unwrap();
        let expected = Array::from_slice(&[5, 1, 6, 6, 2, 7, 7, 3, 8], &[3, 3]);
        assert_array_eq(y, expected, tolerances::EXACT.rtol, tolerances::EXACT.atol);
    }

    #[test]
    fn test_at_least_1d() {
        let x = Array::from_int(1);
        let out = at_least_1d(&x).unwrap();
        assert_eq!(out.ndim(), 1);
        assert_eq!(out.shape(), &[1]);

        let x = Array::from_slice(&[1, 2, 3], &[3]);
        let out = at_least_1d(&x).unwrap();
        assert_eq!(out.ndim(), 1);
        assert_eq!(out.shape(), &[3]);

        let x = Array::from_slice(&[1, 2, 3], &[3, 1]);
        let out = at_least_1d(&x).unwrap();
        assert_eq!(out.ndim(), 2);
        assert_eq!(out.shape(), &[3, 1]);
    }

    #[test]
    fn test_at_least_2d() {
        let x = Array::from_int(1);
        let out = at_least_2d(&x).unwrap();
        assert_eq!(out.ndim(), 2);
        assert_eq!(out.shape(), &[1, 1]);

        let x = Array::from_slice(&[1, 2, 3], &[3]);
        let out = at_least_2d(&x).unwrap();
        assert_eq!(out.ndim(), 2);
        assert_eq!(out.shape(), &[1, 3]);

        let x = Array::from_slice(&[1, 2, 3], &[3, 1]);
        let out = at_least_2d(&x).unwrap();
        assert_eq!(out.ndim(), 2);
        assert_eq!(out.shape(), &[3, 1]);
    }

    #[test]
    fn test_at_least_3d() {
        let x = Array::from_int(1);
        let out = at_least_3d(&x).unwrap();
        assert_eq!(out.ndim(), 3);
        assert_eq!(out.shape(), &[1, 1, 1]);

        let x = Array::from_slice(&[1, 2, 3], &[3]);
        let out = at_least_3d(&x).unwrap();
        assert_eq!(out.ndim(), 3);
        assert_eq!(out.shape(), &[1, 3, 1]);

        let x = Array::from_slice(&[1, 2, 3], &[3, 1]);
        let out = at_least_3d(&x).unwrap();
        assert_eq!(out.ndim(), 3);
        assert_eq!(out.shape(), &[3, 1, 1]);
    }

    #[test]
    fn test_move_axis() {
        let a = Array::from_int(0);
        assert!(move_axis(&a, 0, 0).is_err());

        let a = Array::zeros::<i32>(&[2]).unwrap();
        assert!(move_axis(&a, 0, 1).is_err());
        assert_eq!(move_axis(&a, 0, 0).unwrap().shape(), &[2]);
        assert_eq!(move_axis(&a, -1, -1).unwrap().shape(), &[2]);

        let a = Array::zeros::<i32>(&[2, 3, 4]).unwrap();
        assert!(move_axis(&a, 0, -4).is_err());
        assert!(move_axis(&a, 0, 3).is_err());
        assert!(move_axis(&a, 3, 0).is_err());
        assert!(move_axis(&a, -4, 0).is_err());
        assert_eq!(move_axis(&a, 0, 2).unwrap().shape(), &[3, 4, 2]);
        assert_eq!(move_axis(&a, 0, 1).unwrap().shape(), &[3, 2, 4]);
        assert_eq!(move_axis(&a, 0, -1).unwrap().shape(), &[3, 4, 2]);
        assert_eq!(move_axis(&a, -2, 2).unwrap().shape(), &[2, 4, 3]);
    }

    #[test]
    fn test_concatenate() {
        let a = Array::from_slice(&[1, 2, 3, 4], &[2, 2]);
        let b = Array::from_slice(&[5, 6], &[1, 2]);
        assert_eq!(concatenate(&[&a, &b], 0).unwrap().shape(), &[3, 2]);

        let flat = concatenate_flat(&[&a, &b]).unwrap();
        assert_eq!(flat.shape(), &[6]);
        assert_eq!(flat.as_slice::<i32>(), &[1, 2, 3, 4, 5, 6]);
    }

    #[test]
    fn test_split_equal() {
        let x = Array::from_int(3);
        assert!(split_equal(&x, 0, 0).is_err());

        let x = Array::from_slice(&[0, 1, 2], &[3]);
        assert!(split_equal(&x, 3, 1).is_err());
        assert!(split_equal(&x, -2, 1).is_err());

        let out = split_equal(&x, 3, 0).unwrap();
        assert_eq!(out.len(), 3);

        let mut out = split_equal(&x, 3, -1).unwrap();
        assert_eq!(out.len(), 3);
        for (i, a) in out.iter_mut().enumerate() {
            assert_eq!(a.shape(), &[1]);
            assert_eq!(a.dtype(), Dtype::Int32);
            assert_eq!(a.item_exact::<i32>(), i as i32);
        }

        let x = Array::from_slice(&[0, 1, 2, 3, 4, 5], &[2, 3]);
        let out = split_equal(&x, 2, None).unwrap();
        assert_array_eq(
            &out[0],
            Array::from_slice(&[0, 1, 2], &[1, 3]),
            tolerances::EXACT.rtol,
            tolerances::EXACT.atol,
        );
        assert_array_eq(
            &out[1],
            Array::from_slice(&[3, 4, 5], &[1, 3]),
            tolerances::EXACT.rtol,
            tolerances::EXACT.atol,
        );

        let out = split_equal(&x, 3, 1).unwrap();
        assert_array_eq(
            &out[0],
            Array::from_slice(&[0, 3], &[2, 1]),
            tolerances::EXACT.rtol,
            tolerances::EXACT.atol,
        );
        assert_array_eq(
            &out[1],
            Array::from_slice(&[1, 4], &[2, 1]),
            tolerances::EXACT.rtol,
            tolerances::EXACT.atol,
        );
        assert_array_eq(
            &out[2],
            Array::from_slice(&[2, 5], &[2, 1]),
            tolerances::EXACT.rtol,
            tolerances::EXACT.atol,
        );

        let x = Array::zeros::<i32>(&[8, 12]).unwrap();
        let out = split_equal(&x, 2, None).unwrap();
        assert_eq!(out.len(), 2);
        assert_eq!(out[0].shape(), &[4, 12]);
        assert_eq!(out[1].shape(), &[4, 12]);

        let out = split_equal(&x, 3, 1).unwrap();
        assert_eq!(out.len(), 3);
        assert_eq!(out[0].shape(), &[8, 4]);
        assert_eq!(out[1].shape(), &[8, 4]);
        assert_eq!(out[2].shape(), &[8, 4]);
    }

    #[test]
    fn test_split_at_indices() {
        let x = Array::zeros::<i32>(&[8, 12]).unwrap();

        let out = split_at_indices(&x, &[], None).unwrap();
        assert_eq!(out.len(), 1);
        assert_eq!(out[0].shape(), x.shape());

        let out = split_at_indices(&x, &[3, 7], None).unwrap();
        assert_eq!(out.len(), 3);
        assert_eq!(out[0].shape(), &[3, 12]);
        assert_eq!(out[1].shape(), &[4, 12]);
        assert_eq!(out[2].shape(), &[1, 12]);

        let out = split_at_indices(&x, &[20], None).unwrap();
        assert_eq!(out.len(), 2);
        assert_eq!(out[0].shape(), &[8, 12]);
        assert_eq!(out[1].shape(), &[0, 12]);

        let out = split_at_indices(&x, &[-5], None).unwrap();
        assert_eq!(out[0].shape(), &[3, 12]);
        assert_eq!(out[1].shape(), &[5, 12]);

        let out = split_at_indices(&x, &[2, 8], Some(1)).unwrap();
        assert_eq!(out[0].shape(), &[8, 2]);
        assert_eq!(out[1].shape(), &[8, 6]);
        assert_eq!(out[2].shape(), &[8, 4]);

        let x = Array::from_iter(0i32..5, &[5]);
        let out = split_at_indices(&x, &[2, 1, 2], None).unwrap();
        assert_array_eq(
            &out[0],
            Array::from_slice(&[0, 1], &[2]),
            tolerances::EXACT.rtol,
            tolerances::EXACT.atol,
        );
        assert_array_eq(
            &out[1],
            Array::from_slice::<i32>(&[], &[0]),
            tolerances::EXACT.rtol,
            tolerances::EXACT.atol,
        );
        assert_array_eq(
            &out[2],
            Array::from_slice(&[1], &[1]),
            tolerances::EXACT.rtol,
            tolerances::EXACT.atol,
        );
        assert_array_eq(
            &out[3],
            Array::from_slice(&[2, 3, 4], &[3]),
            tolerances::EXACT.rtol,
            tolerances::EXACT.atol,
        );
    }

    #[test]
    fn test_pad() {
        let x = Array::zeros::<f32>(&[1, 2, 3]).unwrap();
        assert_eq!(pad(&x, 1, None, None).unwrap().shape(), &[3, 4, 5]);
        assert_eq!(pad(&x, (0, 1), None, None).unwrap().shape(), &[2, 3, 4]);
        assert_eq!(
            pad(&x, &[(1, 1), (1, 2), (3, 1)], None, None)
                .unwrap()
                .shape(),
            &[3, 5, 7]
        );
    }

    #[test]
    fn test_stack() {
        let x = Array::from_slice::<f32>(&[], &[0]);
        let x = vec![x];
        assert_eq!(stack(&x, 0).unwrap().shape(), &[1, 0]);
        assert_eq!(stack(&x, 1).unwrap().shape(), &[0, 1]);

        let x = Array::from_slice(&[1, 2, 3], &[3]);
        let x = vec![x];
        assert_eq!(stack(&x, 0).unwrap().shape(), &[1, 3]);
        assert_eq!(stack(&x, 1).unwrap().shape(), &[3, 1]);

        let y = Array::from_slice(&[4, 5, 6], &[3]);
        let mut z = x;
        z.push(y);
        assert_eq!(stack(&z, 0).unwrap().shape(), &[2, 3]);
        assert_eq!(stack(&z, 1).unwrap().shape(), &[3, 2]);
        assert_eq!(stack(&z, -1).unwrap().shape(), &[3, 2]);
        assert_eq!(stack(&z, -2).unwrap().shape(), &[2, 3]);

        let empty: Vec<Array> = Vec::new();
        assert!(stack(&empty, 0).is_err());

        let x = Array::from_slice(&[1, 2, 3], &[3])
            .as_dtype(Dtype::Float16)
            .unwrap();
        let y = Array::from_slice(&[4, 5, 6], &[3])
            .as_dtype(Dtype::Int32)
            .unwrap();
        assert_eq!(stack(&[x, y], 0).unwrap().dtype(), Dtype::Float16);

        let x = Array::from_slice(&[1, 2, 3], &[3])
            .as_dtype(Dtype::Int32)
            .unwrap();
        let y = Array::from_slice(&[4, 5, 6, 7], &[4])
            .as_dtype(Dtype::Int32)
            .unwrap();
        assert!(stack(&[x, y], 0).is_err());
    }

    #[test]
    fn contiguous_materializes_row_major_for_slice_observers() {
        let input = Array::from_slice(&[1_i32, 2, 3, 4, 5, 6], &[2, 3]);
        let transposed = input.transpose().unwrap();
        assert!(matches!(
            transposed.try_as_slice::<i32>(),
            Err(crate::error::AsSliceError::NotContiguous)
        ));

        let contiguous = transposed.contiguous().unwrap();
        assert_eq!(
            contiguous.try_as_slice::<i32>().unwrap(),
            &[1, 4, 2, 5, 3, 6]
        );
        assert!(bool::try_from_op(|res| unsafe {
            mlx_sys::_mlx_array_is_row_contiguous(res, contiguous.as_ptr())
        })
        .unwrap());
    }

    #[test]
    fn contiguous_options_can_retain_column_major_layout() {
        let input = Array::from_slice(&[1_i32, 2, 3, 4, 5, 6], &[2, 3]);
        let transposed = input.transpose().unwrap();
        let contiguous = transposed
            .contiguous_with_options(ContiguousOptions {
                allow_col_major: true,
            })
            .unwrap();
        contiguous.eval().unwrap();

        assert!(!bool::try_from_op(|res| unsafe {
            mlx_sys::_mlx_array_is_row_contiguous(res, contiguous.as_ptr())
        })
        .unwrap());
        assert!(bool::try_from_op(|res| unsafe {
            mlx_sys::_mlx_array_is_col_contiguous(res, contiguous.as_ptr())
        })
        .unwrap());
        assert!(matches!(
            contiguous.try_as_slice::<i32>(),
            Err(crate::error::AsSliceError::NotContiguous)
        ));
    }

    #[test]
    fn test_swap_axes() {
        let a = Array::from_int(0);
        assert!(swap_axes(&a, 0, 0).is_err());

        let a = Array::zeros::<i32>(&[2]).unwrap();
        assert!(swap_axes(&a, 0, 1).is_err());
        assert_eq!(swap_axes(&a, 0, 0).unwrap().shape(), &[2]);
        assert_eq!(swap_axes(&a, -1, -1).unwrap().shape(), &[2]);

        let a = Array::zeros::<i32>(&[2, 3, 4]).unwrap();
        assert!(swap_axes(&a, 0, -4).is_err());
        assert!(swap_axes(&a, 0, 3).is_err());
        assert!(swap_axes(&a, 3, 0).is_err());
        assert!(swap_axes(&a, -4, 0).is_err());
        assert_eq!(swap_axes(&a, 0, 2).unwrap().shape(), &[4, 3, 2]);
        assert_eq!(swap_axes(&a, 0, 1).unwrap().shape(), &[3, 2, 4]);
        assert_eq!(swap_axes(&a, 0, -1).unwrap().shape(), &[4, 3, 2]);
        assert_eq!(swap_axes(&a, -2, 2).unwrap().shape(), &[2, 4, 3]);
    }

    #[test]
    fn test_tile() {
        let x = Array::from_slice(&[1, 2, 3], &[3]);
        let y = tile(&x, &[2]).unwrap();
        let expected = Array::from_slice(&[1, 2, 3, 1, 2, 3], &[6]);
        assert_array_eq(y, expected, tolerances::EXACT.rtol, tolerances::EXACT.atol);

        let x = Array::from_slice(&[1, 2, 3, 4], &[2, 2]);
        let y = tile(&x, &[2]).unwrap();
        let expected = Array::from_slice(&[1, 2, 1, 2, 3, 4, 3, 4], &[2, 4]);
        assert_array_eq(y, expected, tolerances::EXACT.rtol, tolerances::EXACT.atol);

        let x = Array::from_slice(&[1, 2, 3, 4], &[2, 2]);
        let y = tile(&x, &[4, 1]).unwrap();
        let expected =
            Array::from_slice(&[1, 2, 3, 4, 1, 2, 3, 4, 1, 2, 3, 4, 1, 2, 3, 4], &[8, 2]);
        assert_array_eq(y, expected, tolerances::EXACT.rtol, tolerances::EXACT.atol);

        let x = Array::from_slice(&[1, 2, 3, 4], &[2, 2]);
        let y = tile(&x, &[2, 2]).unwrap();
        let expected =
            Array::from_slice(&[1, 2, 1, 2, 3, 4, 3, 4, 1, 2, 1, 2, 3, 4, 3, 4], &[4, 4]);
        assert_array_eq(y, expected, tolerances::EXACT.rtol, tolerances::EXACT.atol);

        let x = Array::from_slice(&[1, 2, 3], &[3]);
        let y = tile(&x, &[2, 2, 2]).unwrap();
        let expected = Array::from_slice(
            &[
                1, 2, 3, 1, 2, 3, 1, 2, 3, 1, 2, 3, 1, 2, 3, 1, 2, 3, 1, 2, 3, 1, 2, 3,
            ],
            &[2, 2, 6],
        );
        assert_array_eq(y, expected, tolerances::EXACT.rtol, tolerances::EXACT.atol);
    }

    #[test]
    fn test_transpose() {
        let x = Array::from_int(1);
        let y = transpose(&x).unwrap();
        assert!(y.shape().is_empty());
        assert_eq!(y.item_exact::<i32>(), 1);
        assert!(transpose_axes(&x, &[0][..]).is_err());
        assert!(transpose_axes(&x, &[1][..]).is_err());

        let x = Array::from_slice(&[1], &[1]);
        let y = transpose(&x).unwrap();
        assert_eq!(y.shape(), &[1]);
        assert_eq!(y.item_exact::<i32>(), 1);

        let y = transpose_axes(&x, &[-1][..]).unwrap();
        assert_eq!(y.shape(), &[1]);
        assert_eq!(y.item_exact::<i32>(), 1);

        assert!(transpose_axes(&x, &[1][..]).is_err());
        assert!(transpose_axes(&x, &[0, 0][..]).is_err());

        let x = Array::from_slice::<i32>(&[], &[0]);
        let y = transpose(&x).unwrap();
        assert_eq!(y.shape(), &[0]);
        y.eval().unwrap();
        assert_eq!(y.size(), 0);

        let x = Array::from_slice(&[1, 2, 3, 4, 5, 6], &[2, 3]);
        let mut y = transpose(&x).unwrap();
        assert_eq!(y.shape(), &[3, 2]);
        y = transpose_axes(&x, &[-1, 0][..]).unwrap();
        assert_eq!(y.shape(), &[3, 2]);
        y = transpose_axes(&x, &[-1, -2][..]).unwrap();
        assert_eq!(y.shape(), &[3, 2]);
        y.eval().unwrap();
        assert_array_eq(
            y,
            Array::from_slice(&[1, 4, 2, 5, 3, 6], &[3, 2]),
            tolerances::EXACT.rtol,
            tolerances::EXACT.atol,
        );

        let y = transpose_axes(&x, &[0, 1][..]).unwrap();
        assert_eq!(y.shape(), &[2, 3]);
        assert_array_eq(y, &x, tolerances::EXACT.rtol, tolerances::EXACT.atol);

        let y = transpose_axes(&x, &[0, -1][..]).unwrap();
        assert_eq!(y.shape(), &[2, 3]);
        assert_array_eq(y, &x, tolerances::EXACT.rtol, tolerances::EXACT.atol);

        assert!(transpose_axes(&x, &[][..]).is_err());
        assert!(transpose_axes(&x, &[0][..]).is_err());
        assert!(transpose_axes(&x, &[0, 0][..]).is_err());
        assert!(transpose_axes(&x, &[0, 0, 0][..]).is_err());
        assert!(transpose_axes(&x, &[0, 1, 1][..]).is_err());

        let x = Array::from_slice(&[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12], &[2, 3, 2]);
        let y = transpose(&x).unwrap();
        assert_eq!(y.shape(), &[2, 3, 2]);
        let expected = Array::from_slice(&[1, 7, 3, 9, 5, 11, 2, 8, 4, 10, 6, 12], &[2, 3, 2]);
        assert_array_eq(y, expected, tolerances::EXACT.rtol, tolerances::EXACT.atol);

        let y = transpose_axes(&x, &[0, 1, 2][..]).unwrap();
        assert_eq!(y.shape(), &[2, 3, 2]);
        assert_array_eq(y, &x, tolerances::EXACT.rtol, tolerances::EXACT.atol);

        let y = transpose_axes(&x, &[1, 0, 2][..]).unwrap();
        assert_eq!(y.shape(), &[3, 2, 2]);
        let expected = Array::from_slice(&[1, 2, 7, 8, 3, 4, 9, 10, 5, 6, 11, 12], &[3, 2, 2]);
        assert_array_eq(y, expected, tolerances::EXACT.rtol, tolerances::EXACT.atol);

        let y = transpose_axes(&x, &[0, 2, 1][..]).unwrap();
        assert_eq!(y.shape(), &[2, 2, 3]);
        let expected = Array::from_slice(&[1, 3, 5, 2, 4, 6, 7, 9, 11, 8, 10, 12], &[2, 2, 3]);
        assert_array_eq(y, expected, tolerances::EXACT.rtol, tolerances::EXACT.atol);

        let mut x = Array::from_slice(&[0, 1, 2, 3, 4, 5, 6, 7], &[4, 2]);
        x = reshape(transpose(&x).unwrap(), &[2, 2, 2]).unwrap();
        let expected = Array::from_slice(&[0, 2, 4, 6, 1, 3, 5, 7], &[2, 2, 2]);
        assert_array_eq(x, expected, tolerances::EXACT.rtol, tolerances::EXACT.atol);

        let mut x = Array::from_slice(&[0, 1, 2, 3, 4, 5, 6, 7], &[1, 4, 1, 2]);
        // assert!(x.flags().row_contiguous);
        x = transpose_axes(&x, &[2, 1, 0, 3][..]).unwrap();
        x.eval().unwrap();
        // assert!(x.flags().row_contiguous);
    }
}