Add parallel sorting and parallel bulk-selection.

Author: n3vu0r

.github/workflows/build.yml

@@ -14,7 +14,7 @@ jobs:
     - name: toolchain
       uses: actions-rs/toolchain@v1
       with:
-        toolchain: 1.58.0
+        toolchain: 1.60.0
         profile: minimal
         components: rustfmt, rust-docs, clippy
         override: true
@@ -32,6 +32,16 @@ jobs:
       with:
         command: test
         args: --no-default-features
+    - name: test-rayon
+      uses: actions-rs/cargo@v1
+      with:
+        command: test
+        args: --features rayon --
+          par::merge_sort::test::stably_sorted
+          par::quick_sort::test::sorted
+          par::partition::test::at_indices
+      env:
+        QUICKCHECK_GENERATOR_SIZE: 1000000
     - name: clippy
       uses: actions-rs/cargo@v1
       with:
@@ -51,6 +61,11 @@ jobs:
       with:
         command: doc
         args: --no-default-features
+    - name: doc-rayon
+      uses: actions-rs/cargo@v1
+      with:
+        command: doc
+        args: --features rayon
     - name: fmt
       uses: actions-rs/cargo@v1
       with:
@@ -82,6 +97,16 @@ jobs:
       with:
         command: test
         args: --no-default-features
+    - name: test-rayon
+      uses: actions-rs/cargo@v1
+      with:
+        command: test
+        args: --features rayon --
+          par::merge_sort::test::stably_sorted
+          par::quick_sort::test::sorted
+          par::partition::test::at_indices
+      env:
+        QUICKCHECK_GENERATOR_SIZE: 1000000
     - name: clippy
       uses: actions-rs/cargo@v1
       with:
@@ -107,6 +132,13 @@ jobs:
         args: --no-default-features
       env:
         RUSTDOCFLAGS: "--cfg docsrs"
+    - name: doc-rayon
+      uses: actions-rs/cargo@v1
+      with:
+        command: doc
+        args: --features rayon
+      env:
+        RUSTDOCFLAGS: "--cfg docsrs"
     - name: fmt
       uses: actions-rs/cargo@v1
       with:
@@ -116,5 +148,4 @@ jobs:
       uses: actions-rs/cargo@v1
       with:
         command: miri
-        args: test
-      if: ${{ false }}
+        args: test -- Slice1Ext

Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 name = "ndarray-slice"
-version = "0.2.1"
-rust-version = "1.58"
+version = "0.2.2"
+rust-version = "1.60"
 edition = "2021"
 authors = ["Rouven Spreckels <[email protected]>"]
 description = """Fast and robust slice-based algorithms (e.g., sorting, selection, search)
@@ -37,15 +37,18 @@ rustdoc-args = ["--cfg", "docsrs"]
 
 [dependencies]
 ndarray = { version = "0.15.6", default-features = false }
+rayon = { version = "1.7.0", optional = true }
 
 [dev-dependencies]
 quickcheck = "1.0.3"
 quickcheck_macros = "1.0.0"
+rand = "0.8.5"
 
 [features]
 default = ["std"]
 alloc = []
 std = ["alloc", "ndarray/std"]
+rayon = ["dep:rayon", "ndarray/rayon", "std"]
 
 [profile.test]
 opt-level = 2

README.md

@@ -15,10 +15,11 @@
 [License]: https://img.shields.io/badge/License-MIT%20OR%20Apache--2.0-blue.svg
 
 Fast and robust slice-based algorithms (e.g., [sorting], [selection], [search]) for
-non-contiguous (sub)views into *n*-dimensional arrays. Reimplements algorithms in [`slice`] for
-[`ndarray`] with arbitrary memory layout (e.g., non-contiguous).
+non-contiguous (sub)views into *n*-dimensional arrays. Reimplements algorithms in [`slice`] and
+[`rayon::slice`] for [`ndarray`] with arbitrary memory layout (e.g., non-contiguous).
 
 [`slice`]: https://doc.rust-lang.org/std/primitive.slice.html
+[`rayon::slice`]: https://docs.rs/rayon/latest/rayon/slice/index.html
 [`ndarray`]: https://docs.rs/ndarray
 
 ## Example
@@ -38,11 +39,12 @@ let mut v = arr2(&[[-5, 4, 1, -3,  2],   // row 0, axis 0
 // Mutable subview into the last column.
 let mut column = v.column_mut(4);
 
-// Due to row-major memory layout, columns are non-contiguous and hence cannot be sorted by
-// viewing them as mutable slices.
+// Due to row-major memory layout, columns are non-contiguous
+// and hence cannot be sorted by viewing them as mutable slices.
 assert_eq!(column.as_slice_mut(), None);
 
-// Instead, sorting is specifically implemented for non-contiguous mutable (sub)views.
+// Instead, sorting is specifically implemented for non-contiguous
+//  mutable (sub)views.
 column.sort_unstable();
 
 assert!(v == arr2(&[[-5, 4, 1, -3, -1],
@@ -87,8 +89,9 @@ See the [release history](RELEASES.md) to keep track of the development.
 
 ## Features
 
-  * `alloc`: Enables stable `sort`/`sort_by`/`sort_by_key`. Enabled by `std`.
-  * `std`: Enables stable `sort_by_cached_key`. Enabled by default.
+  * `alloc` for stable `sort`/`sort_by`/`sort_by_key`. Enabled by `std`.
+  * `std` for stable `sort_by_cached_key`. Enabled by `default` or `rayon`.
+  * `rayon` for parallel `par_sort*`/`par_select_many_nth_unstable*`.
 
 # License
 

RELEASES.md

@@ -1,3 +1,9 @@
+# Version 0.2.2 (2023-04-13)
+
+  * Add `rayon` feature for parallel sorting and parallel bulk-selection.
+  * Guarantee that bulk-selected elements are in the order of their indices.
+  * Half recursive branching of bulk-selection via tail call elimination.
+
 # Version 0.2.1 (2023-04-08)
 
   * Update docs.