Merge branch '3-return-array-or-vector-from-c' into 'master'

Resolve "return array or vector from C"

Closes #3

See merge request !5

src/main.cpp

@@ -32,6 +32,40 @@ double sum_2d_array(const std::vector<std::vector<double>> &arr) {
     return sum;
 }
 
+std::vector<double> sum_rows(const std::vector<std::vector<double>> &arr) {
+    std::vector<double> row_sums;
+    for (const auto &row : arr) {
+        double row_sum = 0;
+        for (double num : row) {
+            row_sum += num;
+        }
+        row_sums.push_back(row_sum);
+    }
+    return row_sums;
+}
+
+std::vector<std::vector<double>> matrix_multiply(const std::vector<std::vector<double>> &arr1, const std::vector<std::vector<double>> &arr2) {
+    int m1 = arr1.size();
+    int n1 = arr1[0].size();
+    int m2 = arr2.size();
+    int n2 = arr2[0].size();
+
+    if (n1 != m2) {
+        throw std::invalid_argument("Matrices cannot be multiplied due to incompatible dimensions");
+    }
+    std::vector<std::vector<double>> result(m1, std::vector<double>(n2, 0));
+
+    for (int i = 0; i < m1; ++i) {
+        for (int j = 0; j < n2; ++j) {
+            for (int k = 0; k < n1; ++k) {
+                result[i][j] += arr1[i][k] * arr2[k][j];
+            }
+        }
+    }
+
+    return result;
+}
+
 
 namespace py = pybind11;
 
@@ -68,6 +102,8 @@ PYBIND11_MODULE(_core, m) {
 
     m.def("sum_array", &sum_array, "Calculate the sum of elements in an array");
     m.def("sum_2d_array", &sum_2d_array, "Calculate the sum of elements in a 2D array");
+    m.def("sum_rows", &sum_rows, "Calculate the sum of elements in each row of a 2D array");
+    m.def("matrix_multiply", &matrix_multiply, "Perform matrix multiplication of two 2D arrays");
 
 #ifdef VERSION_INFO
     m.attr("__version__") = MACRO_STRINGIFY(VERSION_INFO);

src/pybind_example/__init__.py

@@ -8,6 +8,8 @@ from ._core import (
     multiply,
     sum_array,
     sum_2d_array,
+    sum_rows,
+    matrix_multiply,
 )
 
 __all__ = [
@@ -18,4 +20,6 @@ __all__ = [
     "multiply",
     "sum_array",
     "sum_2d_array",
+    "sum_rows",
+    "matrix_multiply",
 ]

tests/test_basic.py

@@ -2,7 +2,7 @@ from __future__ import annotations
 
 import pybind_example as m
 import numpy as np
-
+import pytest
 
 def test_version():
     assert m.__version__ == "0.0.1"
@@ -32,5 +32,26 @@ def test_sum_array_numpy_array_1D_int():
 
 
 def test_sum_array_numpy_array_2D_float():
-    array = np.arange(9).reshape((3,3))
+    array = np.arange(9).reshape((3, 3))
     assert m.sum_2d_array(array) == np.sum(array)
+
+
+def test_sum_rows_numpy_array():
+    array = np.arange(9).reshape((3, 3))
+    np.testing.assert_array_almost_equal(m.sum_rows(array), np.sum(array, axis=1))
+
+
+def test_matrix_multiply_1():
+    array_1 = np.asarray([[1, 2], [3, 4]])
+    array_2 = np.asarray([[5, 6], [7, 8]])
+    np.testing.assert_array_almost_equal(
+        m.matrix_multiply(array_1, array_2), array_1 @ array_2
+    )
+
+def test_matrix_multiply_raise():
+    array_1 = np.asarray([[1, 2, 6], [3, 4, 5]])
+    array_2 = np.asarray([[5, 6, 1], [7, 8, 1]])
+    with pytest.raises(ValueError) as e:
+        m.matrix_multiply(array_1, array_2)
+        assert str(e) == "Matrices cannot be multiplied due to incompatible dimensions"
+