concatenate bins

pyfar/utils.py

@@ -212,3 +212,45 @@ def concatenate_channels(signals, caxis=0, broadcasting=False):
         return pf.TimeData(data, signals[0].times)
     else:
         return pf.FrequencyData(data, signals[0].frequencies)
+
+
+def concatenate_bins(signals):
+    """
+    Merge multiple FrequencyData objects along the frequency axe.
+
+    Parameters
+    ----------
+    signals : tuple of FrequencyData
+        The signals to concatenate. All signals must have the same cshape.
+        the frequency bins get sorted and doubles are removed, the first
+        entry is used.
+
+    Returns
+    -------
+    merged : FrequencyData
+        The merged signal object.
+    """
+    # check input
+    if not isinstance(signals, (tuple, list)):
+        raise TypeError(
+            "Input must be a tuple or list of pf.FrequencyData objects.")
+
+    for signal in signals:
+        if not isinstance(signal, (pf.FrequencyData)):
+            raise TypeError(
+                "All input data must be of type pf.FrequencyData.")
+
+    # check matching meta data of input signals.
+    [signals[0]._assert_matching_meta_data(s) for s in signals]
+
+    # concatenate data
+    data = np.concatenate([s.freq for s in signals], axis=-1)
+    frequencies = np.concatenate([s.frequencies for s in signals], axis=-1)
+
+    # Sort frequency entries
+    idx = np.argsort(frequencies)
+    frequencies = frequencies[idx]
+    data = data[..., idx]
+
+    # return merged Signal
+    return pf.FrequencyData(data, frequencies)

tests/test_utils.py

@@ -160,3 +160,73 @@ def test_concatenate_assertions():
                pf.TimeData([1, 2, 3], [1, 2, 3]))
     with pytest.raises(ValueError, match="Comparison only valid against"):
         pf.utils.concatenate_channels(signals)
+
+
+def test_concatenate_bins_frequencydata():
+    """Test concatenate_bins function with FrequencyData objects"""
+    signals = (
+        pf.FrequencyData([1, 2, 3], [1, 2, 3]),
+        pf.FrequencyData([4, 5, 6], [4, 5, 6]))
+    merged = pf.utils.concatenate_bins(signals)
+    assert isinstance(merged, pf.FrequencyData)
+    npt.assert_array_equal(merged.frequencies, np.arange(1, 7))
+
+
+def test_concatenate_bins_frequencydata_with_sort():
+    """Test concatenate_bins function with FrequencyData objects"""
+    signals = (
+        pf.FrequencyData([1, 3, 5], [1, 3, 5]),
+        pf.FrequencyData([2, 4, 6], [2, 4, 6]))
+    merged = pf.utils.concatenate_bins(signals)
+    assert isinstance(merged, pf.FrequencyData)
+    npt.assert_array_equal(merged.frequencies, np.arange(1, 7))
+    npt.assert_array_equal(merged.freq, np.arange(1, 7).reshape((1, 6)))
+
+
+def test_concatenate_bins_multidim():
+    """Test concatenate_bins function with multidimensional input"""
+    signals = (
+        pf.FrequencyData(np.array([[1, 2, 3], [4, 5, 6]]), [1, 2, 3]),
+        pf.FrequencyData(np.array([[7, 8, 9], [10, 11, 12]]), [4, 5, 6]))
+    merged = pf.utils.concatenate_bins(signals)
+    assert isinstance(merged, pf.FrequencyData)
+    npt.assert_array_equal(merged.frequencies, np.arange(1, 7))
+    npt.assert_array_equal(merged.freq, np.array(
+        [[1, 2, 3, 7, 8, 9], [4, 5, 6, 10, 11, 12]]))
+
+
+def test_concatenate_bins_multidim_with_sort():
+    """Test concatenate_bins function with multidimensional
+    input and unsorted frequencies"""
+    signals = (
+        pf.FrequencyData(np.array([[1, 3, 5], [7, 9, 11]]), [1, 3, 5]),
+        pf.FrequencyData(np.array([[2, 4, 6], [8, 10, 12]]), [2, 4, 6]))
+    merged = pf.utils.concatenate_bins(signals)
+    assert isinstance(merged, pf.FrequencyData)
+    npt.assert_array_equal(merged.frequencies, np.arange(1, 7))
+    npt.assert_array_equal(merged.freq, np.array(
+        [[1, 2, 3, 4, 5, 6], [7, 8, 9, 10, 11, 12]]))
+
+
+def test_concatenate_bins_assertions():
+    """Test assertions"""
+    # invalid input type
+    with pytest.raises(
+            TypeError,
+            match="All input data must be of type pf.FrequencyData."):
+        pf.utils.concatenate_bins([1, 2, 3])
+
+
+def test_input_type():
+    # Create some FrequencyData objects for testing
+    signal1 = pf.FrequencyData(np.random.rand(10), np.arange(10))
+    signal3 = "not a FrequencyData object"
+
+    # Test that a TypeError is raised if the input is not a tuple
+    with pytest.raises(TypeError):
+        pf.utils.concatenate_bins(signal1)
+
+    # Test that a TypeError is raised if the input is not a
+    # tuple of FrequencyData objects
+    with pytest.raises(TypeError):
+        pf.utils.concatenate_bins((signal1, signal3))