ndarray-gen: Add simple internal interface for building matrices

Author: bluss

Cargo.toml

@@ -85,6 +85,7 @@ members = [
 default-members = [
     ".",
     "ndarray-rand",
+    "crates/ndarray-gen",
     "crates/numeric-tests",
     "crates/serialization-tests",
     # exclude blas-tests that depends on BLAS install
@@ -93,6 +94,7 @@ default-members = [
 [workspace.dependencies]
 ndarray = { version = "0.16", path = "." }
 ndarray-rand = { path = "ndarray-rand" }
+ndarray-gen = { path = "crates/ndarray-gen" }
 
 num-integer = { version = "0.1.39", default-features = false }
 num-traits = { version = "0.2", default-features = false }

crates/ndarray-gen/Cargo.toml

@@ -0,0 +1,9 @@
+[package]
+name = "ndarray-gen"
+version = "0.1.0"
+edition = "2018"
+publish = false
+
+[dependencies]
+ndarray = { workspace = true }
+num-traits = { workspace = true }

crates/ndarray-gen/README.md

@@ -0,0 +1,4 @@
+
+## ndarray-gen
+
+Array generation functions, used for testing.

crates/ndarray-gen/src/array_builder.rs

@@ -0,0 +1,97 @@
+// Copyright 2024 bluss and ndarray developers.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+use ndarray::Array;
+use ndarray::Dimension;
+use ndarray::IntoDimension;
+use ndarray::Order;
+
+use num_traits::Num;
+
+#[derive(Copy, Clone, Debug, PartialEq, Eq)]
+pub struct ArrayBuilder<D: Dimension>
+{
+    dim: D,
+    memory_order: Order,
+    generator: ElementGenerator,
+}
+
+/// How to generate elements
+#[derive(Copy, Clone, Debug, PartialEq, Eq)]
+pub enum ElementGenerator
+{
+    Sequential,
+    Zero,
+}
+
+impl<D: Dimension> Default for ArrayBuilder<D>
+{
+    fn default() -> Self
+    {
+        Self::new(D::zeros(D::NDIM.unwrap_or(1)))
+    }
+}
+
+impl<D> ArrayBuilder<D>
+where D: Dimension
+{
+    pub fn new(dim: impl IntoDimension<Dim = D>) -> Self
+    {
+        ArrayBuilder {
+            dim: dim.into_dimension(),
+            memory_order: Order::C,
+            generator: ElementGenerator::Sequential,
+        }
+    }
+
+    pub fn memory_order(mut self, order: Order) -> Self
+    {
+        self.memory_order = order;
+        self
+    }
+
+    pub fn generator(mut self, generator: ElementGenerator) -> Self
+    {
+        self.generator = generator;
+        self
+    }
+
+    pub fn build<T>(self) -> Array<T, D>
+    where T: Num + Clone
+    {
+        let mut current = T::zero();
+        let size = self.dim.size();
+        let use_zeros = self.generator == ElementGenerator::Zero;
+        Array::from_iter((0..size).map(|_| {
+            let ret = current.clone();
+            if !use_zeros {
+                current = ret.clone() + T::one();
+            }
+            ret
+        }))
+        .into_shape_with_order((self.dim, self.memory_order))
+        .unwrap()
+    }
+}
+
+#[test]
+fn test_order()
+{
+    let (m, n) = (12, 13);
+    let c = ArrayBuilder::new((m, n))
+        .memory_order(Order::C)
+        .build::<i32>();
+    let f = ArrayBuilder::new((m, n))
+        .memory_order(Order::F)
+        .build::<i32>();
+
+    assert_eq!(c.shape(), &[m, n]);
+    assert_eq!(f.shape(), &[m, n]);
+    assert_eq!(c.strides(), &[n as isize, 1]);
+    assert_eq!(f.strides(), &[1, m as isize]);
+}

crates/ndarray-gen/src/lib.rs

@@ -0,0 +1,11 @@
+// Copyright 2024 bluss and ndarray developers.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+/// Build ndarray arrays for test purposes
+
+pub mod array_builder;