diff --git a/pyqtgraph/functions.py b/pyqtgraph/functions.py index 187a4717..32d9f2bf 100644 --- a/pyqtgraph/functions.py +++ b/pyqtgraph/functions.py @@ -536,12 +536,15 @@ def interpolateArray(data, x, default=0.0, order=1): N-dimensional interpolation similar to scipy.ndimage.map_coordinates. This function returns linearly-interpolated values sampled from a regular - grid of data. + grid of data. It differs from `ndimage.map_coordinates` by allowing broadcasting + within the input array. ============== =========================================================================================== **Arguments:** *data* Array of any shape containing the values to be interpolated. - *x* Array with (shape[-1] <= data.ndim) containing the locations within *data* to interpolate. + *x* Array with (shape[-1] <= data.ndim) containing the locations within *data* to interpolate. + (note: the axes for this argument are transposed relative to the same argument for + `ndimage.map_coordinates`). *default* Value to return for locations in *x* that are outside the bounds of *data*. *order* Order of interpolation: 0=nearest, 1=linear. ============== =========================================================================================== diff --git a/pyqtgraph/tests/test_functions.py b/pyqtgraph/tests/test_functions.py index bfa7e0ea..4c9cabfe 100644 --- a/pyqtgraph/tests/test_functions.py +++ b/pyqtgraph/tests/test_functions.py @@ -22,9 +22,17 @@ def testSolve3D(): assert_array_almost_equal(tr[:3], tr2[:3]) -def test_interpolateArray(): +def test_interpolateArray_order0(): + check_interpolateArray(order=0) + + +def test_interpolateArray_order1(): + check_interpolateArray(order=1) + + +def check_interpolateArray(order): def interpolateArray(data, x): - result = pg.interpolateArray(data, x) + result = pg.interpolateArray(data, x, order=order) assert result.shape == x.shape[:-1] + data.shape[x.shape[-1]:] return result @@ -48,7 +56,6 @@ def test_interpolateArray(): with pytest.raises(TypeError): interpolateArray(data, np.ones((5, 5, 3,))) - x = np.array([[ 0.3, 0.6], [ 1. , 1. ], [ 0.5, 1. ], @@ -56,9 +63,10 @@ def test_interpolateArray(): [ 10. , 10. ]]) result = interpolateArray(data, x) - #import scipy.ndimage - #spresult = scipy.ndimage.map_coordinates(data, x.T, order=1) - spresult = np.array([ 5.92, 20. , 11. , 0. , 0. ]) # generated with the above line + # make sure results match ndimage.map_coordinates + import scipy.ndimage + spresult = scipy.ndimage.map_coordinates(data, x.T, order=order) + #spresult = np.array([ 5.92, 20. , 11. , 0. , 0. ]) # generated with the above line assert_array_almost_equal(result, spresult) @@ -78,24 +86,13 @@ def test_interpolateArray(): [[1.5, 0.5], [1.5, 1.0], [1.5, 1.5]]]) r1 = interpolateArray(data, x) - #r2 = scipy.ndimage.map_coordinates(data, x.transpose(2,0,1), order=1) - r2 = np.array([[ 8.25, 11. , 16.5 ], # generated with the above line - [ 82.5 , 110. , 165. ]]) + r2 = scipy.ndimage.map_coordinates(data, x.transpose(2,0,1), order=order) + #r2 = np.array([[ 8.25, 11. , 16.5 ], # generated with the above line + #[ 82.5 , 110. , 165. ]]) assert_array_almost_equal(r1, r2) - # test interpolate where data.ndim > x.shape[1] - - data = np.array([[[1, 2, 3], [4, 5, 6]], [[7, 8, 9], [10, 11, 12]]]) # 2x2x3 - x = np.array([[1, 1], [0, 0.5], [5, 5]]) - - r1 = interpolateArray(data, x) - assert np.all(r1[0] == data[1, 1]) - assert np.all(r1[1] == 0.5 * (data[0, 0] + data[0, 1])) - assert np.all(r1[2] == 0) - - def test_subArray(): a = np.array([0, 0, 111, 112, 113, 0, 121, 122, 123, 0, 0, 0, 211, 212, 213, 0, 221, 222, 223, 0, 0, 0, 0]) b = pg.subArray(a, offset=2, shape=(2,2,3), stride=(10,4,1))