clib.conversion.vectors_to_arrays: Move inline doctests into a separa…

…te test file (#3549)

Co-authored-by: Wei Ji <[email protected]>

pygmt/clib/conversion.py

@@ -168,41 +168,7 @@ def vectors_to_arrays(vectors: Sequence[Any]) -> list[np.ndarray]:
     True
     >>> all(isinstance(i, np.ndarray) for i in arrays)
     True
-
-    >>> data = [[1, 2], (3, 4), range(5, 7)]
-    >>> all(isinstance(i, np.ndarray) for i in vectors_to_arrays(data))
-    True
-
-    >>> # Sequence of scalars are converted to 1-D arrays
-    >>> data = vectors_to_arrays([1, 2, 3.0])
-    >>> data
-    [array([1]), array([2]), array([3.])]
-    >>> [i.ndim for i in data]  # Check that they are 1-D arrays
-    [1, 1, 1]
-
-    >>> series = pd.Series(data=[0, 4, pd.NA, 8, 6], dtype=pd.Int32Dtype())
-    >>> vectors_to_arrays([series])
-    [array([ 0.,  4., nan,  8.,  6.])]
-
-    >>> import datetime
-    >>> import pytest
-    >>> pa = pytest.importorskip("pyarrow")
-    >>> vectors = [
-    ...     pd.Series(
-    ...         data=[datetime.date(2020, 1, 1), datetime.date(2021, 12, 31)],
-    ...         dtype="date32[day][pyarrow]",
-    ...     ),
-    ...     pd.Series(
-    ...         data=[datetime.date(2022, 1, 1), datetime.date(2023, 12, 31)],
-    ...         dtype="date64[ms][pyarrow]",
-    ...     ),
-    ... ]
-    >>> arrays = vectors_to_arrays(vectors)
-    >>> all(a.flags.c_contiguous for a in arrays)
-    True
-    >>> all(isinstance(a, np.ndarray) for a in arrays)
-    True
-    >>> all(isinstance(a.dtype, np.dtypes.DateTime64DType) for a in arrays)
+    >>> all(i.ndim == 1 for i in arrays)
     True
     """
     dtypes = {

pygmt/tests/test_clib_vectors_to_arrays.py

@@ -0,0 +1,102 @@
+"""
+Test the vectors_to_arrays function in the clib.conversion module.
+"""
+
+import datetime
+import importlib
+
+import numpy as np
+import numpy.testing as npt
+import pandas as pd
+import pytest
+from pygmt.clib.conversion import vectors_to_arrays
+
+_HAS_PYARROW = bool(importlib.util.find_spec("pyarrow"))
+
+
+def _check_arrays(arrays):
+    """
+    A helper function to check the results of vectors_to_arrays.
+
+    - Check if all arrays are C-contiguous
+    - Check if all arrays are numpy arrays
+    - Check if all arrays are 1-D
+    """
+    # Check if all arrays are C-contiguous
+    assert all(i.flags.c_contiguous for i in arrays)
+    # Check if all arrays are numpy arrays
+    assert all(isinstance(i, np.ndarray) for i in arrays)
+    # Check if all arrays are 1-D
+    assert all(i.ndim == 1 for i in arrays)
+
+
+@pytest.mark.parametrize(
+    "vectors",
+    [
+        pytest.param([[1, 2], (3, 4), range(5, 7)], id="python_sequences"),
+        pytest.param(
+            [np.array([1, 2]), np.array([3, 4]), np.array([5, 6])], id="numpy_arrays"
+        ),
+        pytest.param([[1, 2], np.array([3, 4]), range(5, 7)], id="mixed_sequences"),
+    ],
+)
+def test_vectors_to_arrays(vectors):
+    """
+    Test the vectors_to_arrays function for various input types.
+    """
+    arrays = vectors_to_arrays(vectors)
+    npt.assert_equal(arrays, [np.array([1, 2]), np.array([3, 4]), np.array([5, 6])])
+    _check_arrays(arrays)
+
+
+def test_vectors_to_arrays_scalars():
+    """
+    Test that the vectors_to_arrays function can deal with 0-D scalars.
+    """
+    arrays = vectors_to_arrays([1, 2, 3.0])
+    npt.assert_equal(arrays, [np.array([1]), np.array([2]), np.array([3.0])])
+    _check_arrays(arrays)
+
+
+def test_vectors_to_arrays_not_c_contiguous():
+    """
+    Test the vectors_to_arrays function with numpy arrays that are not C-contiguous.
+    """
+    data = np.array([[1, 2], [3, 4], [5, 6]])
+    vectors = [data[:, 0], data[:, 1]]
+    assert all(not i.flags.c_contiguous for i in vectors)
+    arrays = vectors_to_arrays(vectors)
+    _check_arrays(arrays)
+
+
+def test_vectors_to_arrays_pandas_nan():
+    """
+    Test the vectors_to_arrays function with pandas Series containing NaNs.
+    """
+    vectors = [pd.Series(data=[0, 4, pd.NA, 8, 6], dtype=pd.Int32Dtype())]
+    arrays = vectors_to_arrays(vectors)
+    npt.assert_equal(
+        arrays[0], np.array([0, 4, np.nan, 8, 6], dtype=np.float64), strict=True
+    )
+    _check_arrays(arrays)
+
+
+@pytest.mark.skipif(not _HAS_PYARROW, reason="pyarrow is not installed.")
+def test_vectors_to_arrays_pyarrow_datetime():
+    """
+    Test the vectors_to_arrays function with pyarrow arrays containing date32/date64
+    types.
+    """
+    vectors = [
+        pd.Series(
+            data=[datetime.date(2020, 1, 1), datetime.date(2021, 12, 31)],
+            dtype="date32[day][pyarrow]",
+        ),
+        pd.Series(
+            data=[datetime.date(2022, 1, 1), datetime.date(2023, 12, 31)],
+            dtype="date64[ms][pyarrow]",
+        ),
+    ]
+    arrays = vectors_to_arrays(vectors)
+    assert all(i.dtype.type == np.datetime64 for i in arrays)
+    _check_arrays(arrays)