name : test_index_tricks.py import pytest import numpy as np from numpy.testing import ( assert_, assert_equal, assert_array_equal, assert_almost_equal, assert_array_almost_equal, assert_raises, assert_raises_regex, ) from numpy.lib.index_tricks import ( mgrid, ogrid, ndenumerate, fill_diagonal, diag_indices, diag_indices_from, index_exp, ndindex, r_, s_, ix_ ) class TestRavelUnravelIndex: def test_basic(self): assert_equal(np.unravel_index(2, (2, 2)), (1, 0)) # test that new shape argument works properly assert_equal(np.unravel_index(indices=2, shape=(2, 2)), (1, 0)) # test that an invalid second keyword argument # is properly handled, including the old name `dims`. with assert_raises(TypeError): np.unravel_index(indices=2, hape=(2, 2)) with assert_raises(TypeError): np.unravel_index(2, hape=(2, 2)) with assert_raises(TypeError): np.unravel_index(254, ims=(17, 94)) with assert_raises(TypeError): np.unravel_index(254, dims=(17, 94)) assert_equal(np.ravel_multi_index((1, 0), (2, 2)), 2) assert_equal(np.unravel_index(254, (17, 94)), (2, 66)) assert_equal(np.ravel_multi_index((2, 66), (17, 94)), 254) assert_raises(ValueError, np.unravel_index, -1, (2, 2)) assert_raises(TypeError, np.unravel_index, 0.5, (2, 2)) assert_raises(ValueError, np.unravel_index, 4, (2, 2)) assert_raises(ValueError, np.ravel_multi_index, (-3, 1), (2, 2)) assert_raises(ValueError, np.ravel_multi_index, (2, 1), (2, 2)) assert_raises(ValueError, np.ravel_multi_index, (0, -3), (2, 2)) assert_raises(ValueError, np.ravel_multi_index, (0, 2), (2, 2)) assert_raises(TypeError, np.ravel_multi_index, (0.1, 0.), (2, 2)) assert_equal(np.unravel_index((2*3 + 1)*6 + 4, (4, 3, 6)), [2, 1, 4]) assert_equal( np.ravel_multi_index([2, 1, 4], (4, 3, 6)), (2*3 + 1)*6 + 4) arr = np.array([[3, 6, 6], [4, 5, 1]]) assert_equal(np.ravel_multi_index(arr, (7, 6)), [22, 41, 37]) assert_equal( np.ravel_multi_index(arr, (7, 6), order='F'), [31, 41, 13]) assert_equal( np.ravel_multi_index(arr, (4, 6), mode='clip'), [22, 23, 19]) assert_equal(np.ravel_multi_index(arr, (4, 4), mode=('clip', 'wrap')), [12, 13, 13]) assert_equal(np.ravel_multi_index((3, 1, 4, 1), (6, 7, 8, 9)), 1621) assert_equal(np.unravel_index(np.array([22, 41, 37]), (7, 6)), [[3, 6, 6], [4, 5, 1]]) assert_equal( np.unravel_index(np.array([31, 41, 13]), (7, 6), order='F'), [[3, 6, 6], [4, 5, 1]]) assert_equal(np.unravel_index(1621, (6, 7, 8, 9)), [3, 1, 4, 1]) def test_empty_indices(self): msg1 = 'indices must be integral: the provided empty sequence was' msg2 = 'only int indices permitted' assert_raises_regex(TypeError, msg1, np.unravel_index, [], (10, 3, 5)) assert_raises_regex(TypeError, msg1, np.unravel_index, (), (10, 3, 5)) assert_raises_regex(TypeError, msg2, np.unravel_index, np.array([]), (10, 3, 5)) assert_equal(np.unravel_index(np.array([],dtype=int), (10, 3, 5)), [[], [], []]) assert_raises_regex(TypeError, msg1, np.ravel_multi_index, ([], []), (10, 3)) assert_raises_regex(TypeError, msg1, np.ravel_multi_index, ([], ['abc']), (10, 3)) assert_raises_regex(TypeError, msg2, np.ravel_multi_index, (np.array([]), np.array([])), (5, 3)) assert_equal(np.ravel_multi_index( (np.array([], dtype=int), np.array([], dtype=int)), (5, 3)), []) assert_equal(np.ravel_multi_index(np.array([[], []], dtype=int), (5, 3)), []) def test_big_indices(self): # ravel_multi_index for big indices (issue #7546) if np.intp == np.int64: arr = ([1, 29], [3, 5], [3, 117], [19, 2], [2379, 1284], [2, 2], [0, 1]) assert_equal( np.ravel_multi_index(arr, (41, 7, 120, 36, 2706, 8, 6)), [5627771580, 117259570957]) # test unravel_index for big indices (issue #9538) assert_raises(ValueError, np.unravel_index, 1, (2**32-1, 2**31+1)) # test overflow checking for too big array (issue #7546) dummy_arr = ([0],[0]) half_max = np.iinfo(np.intp).max // 2 assert_equal( np.ravel_multi_index(dummy_arr, (half_max, 2)), [0]) assert_raises(ValueError, np.ravel_multi_index, dummy_arr, (half_max+1, 2)) assert_equal( np.ravel_multi_index(dummy_arr, (half_max, 2), order='F'), [0]) assert_raises(ValueError, np.ravel_multi_index, dummy_arr, (half_max+1, 2), order='F') def test_dtypes(self): # Test with different data types for dtype in [np.int16, np.uint16, np.int32, np.uint32, np.int64, np.uint64]: coords = np.array( [[1, 0, 1, 2, 3, 4], [1, 6, 1, 3, 2, 0]], dtype=dtype) shape = (5, 8) uncoords = 8*coords[0]+coords[1] assert_equal(np.ravel_multi_index(coords, shape), uncoords) assert_equal(coords, np.unravel_index(uncoords, shape)) uncoords = coords[0]+5*coords[1] assert_equal( np.ravel_multi_index(coords, shape, order='F'), uncoords) assert_equal(coords, np.unravel_index(uncoords, shape, order='F')) coords = np.array( [[1, 0, 1, 2, 3, 4], [1, 6, 1, 3, 2, 0], [1, 3, 1, 0, 9, 5]], dtype=dtype) shape = (5, 8, 10) uncoords = 10*(8*coords[0]+coords[1])+coords[2] assert_equal(np.ravel_multi_index(coords, shape), uncoords) assert_equal(coords, np.unravel_index(uncoords, shape)) uncoords = coords[0]+5*(coords[1]+8*coords[2]) assert_equal( np.ravel_multi_index(coords, shape, order='F'), uncoords) assert_equal(coords, np.unravel_index(uncoords, shape, order='F')) def test_clipmodes(self): # Test clipmodes assert_equal( np.ravel_multi_index([5, 1, -1, 2], (4, 3, 7, 12), mode='wrap'), np.ravel_multi_index([1, 1, 6, 2], (4, 3, 7, 12))) assert_equal(np.ravel_multi_index([5, 1, -1, 2], (4, 3, 7, 12), mode=( 'wrap', 'raise', 'clip', 'raise')), np.ravel_multi_index([1, 1, 0, 2], (4, 3, 7, 12))) assert_raises( ValueError, np.ravel_multi_index, [5, 1, -1, 2], (4, 3, 7, 12)) def test_writeability(self): # See gh-7269 x, y = np.unravel_index([1, 2, 3], (4, 5)) assert_(x.flags.writeable) assert_(y.flags.writeable) def test_0d(self): # gh-580 x = np.unravel_index(0, ()) assert_equal(x, ()) assert_raises_regex(ValueError, "0d array", np.unravel_index, [0], ()) assert_raises_regex( ValueError, "out of bounds", np.unravel_index, [1], ()) @pytest.mark.parametrize("mode", ["clip", "wrap", "raise"]) def test_empty_array_ravel(self, mode): res = np.ravel_multi_index( np.zeros((3, 0), dtype=np.intp), (2, 1, 0), mode=mode) assert(res.shape == (0,)) with assert_raises(ValueError): np.ravel_multi_index( np.zeros((3, 1), dtype=np.intp), (2, 1, 0), mode=mode) def test_empty_array_unravel(self): res = np.unravel_index(np.zeros(0, dtype=np.intp), (2, 1, 0)) # res is a tuple of three empty arrays assert(len(res) == 3) assert(all(a.shape == (0,) for a in res)) with assert_raises(ValueError): np.unravel_index([1], (2, 1, 0)) class TestGrid: def test_basic(self): a = mgrid[-1:1:10j] b = mgrid[-1:1:0.1] assert_(a.shape == (10,)) assert_(b.shape == (20,)) assert_(a[0] == -1) assert_almost_equal(a[-1], 1) assert_(b[0] == -1) assert_almost_equal(b[1]-b[0], 0.1, 11) assert_almost_equal(b[-1], b[0]+19*0.1, 11) assert_almost_equal(a[1]-a[0], 2.0/9.0, 11) def test_linspace_equivalence(self): y, st = np.linspace(2, 10, retstep=True) assert_almost_equal(st, 8/49.0) assert_array_almost_equal(y, mgrid[2:10:50j], 13) def test_nd(self): c = mgrid[-1:1:10j, -2:2:10j] d = mgrid[-1:1:0.1, -2:2:0.2] assert_(c.shape == (2, 10, 10)) assert_(d.shape == (2, 20, 20)) assert_array_equal(c[0][0, :], -np.ones(10, 'd')) assert_array_equal(c[1][:, 0], -2*np.ones(10, 'd')) assert_array_almost_equal(c[0][-1, :], np.ones(10, 'd'), 11) assert_array_almost_equal(c[1][:, -1], 2*np.ones(10, 'd'), 11) assert_array_almost_equal(d[0, 1, :] - d[0, 0, :], 0.1*np.ones(20, 'd'), 11) assert_array_almost_equal(d[1, :, 1] - d[1, :, 0], 0.2*np.ones(20, 'd'), 11) def test_sparse(self): grid_full = mgrid[-1:1:10j, -2:2:10j] grid_sparse = ogrid[-1:1:10j, -2:2:10j] # sparse grids can be made dense by broadcasting grid_broadcast = np.broadcast_arrays(*grid_sparse) for f, b in zip(grid_full, grid_broadcast): assert_equal(f, b) @pytest.mark.parametrize("start, stop, step, expected", [ (None, 10, 10j, (200, 10)), (-10, 20, None, (1800, 30)), ]) def test_mgrid_size_none_handling(self, start, stop, step, expected): # regression test None value handling for # start and step values used by mgrid; # internally, this aims to cover previously # unexplored code paths in nd_grid() grid = mgrid[start:stop:step, start:stop:step] # need a smaller grid to explore one of the # untested code paths grid_small = mgrid[start:stop:step] assert_equal(grid.size, expected[0]) assert_equal(grid_small.size, expected[1]) def test_accepts_npfloating(self): # regression test for #16466 grid64 = mgrid[0.1:0.33:0.1, ] grid32 = mgrid[np.float32(0.1):np.float32(0.33):np.float32(0.1), ] assert_(grid32.dtype == np.float64) assert_array_almost_equal(grid64, grid32) # different code path for single slice grid64 = mgrid[0.1:0.33:0.1] grid32 = mgrid[np.float32(0.1):np.float32(0.33):np.float32(0.1)] assert_(grid32.dtype == np.float64) assert_array_almost_equal(grid64, grid32) def test_accepts_longdouble(self): # regression tests for #16945 grid64 = mgrid[0.1:0.33:0.1, ] grid128 = mgrid[ np.longdouble(0.1):np.longdouble(0.33):np.longdouble(0.1), ] assert_(grid128.dtype == np.longdouble) assert_array_almost_equal(grid64, grid128) grid128c_a = mgrid[0:np.longdouble(1):3.4j] grid128c_b = mgrid[0:np.longdouble(1):3.4j, ] assert_(grid128c_a.dtype == grid128c_b.dtype == np.longdouble) assert_array_equal(grid128c_a, grid128c_b[0]) # different code path for single slice grid64 = mgrid[0.1:0.33:0.1] grid128 = mgrid[ np.longdouble(0.1):np.longdouble(0.33):np.longdouble(0.1) ] assert_(grid128.dtype == np.longdouble) assert_array_almost_equal(grid64, grid128) def test_accepts_npcomplexfloating(self): # Related to #16466 assert_array_almost_equal( mgrid[0.1:0.3:3j, ], mgrid[0.1:0.3:np.complex64(3j), ] ) # different code path for single slice assert_array_almost_equal( mgrid[0.1:0.3:3j], mgrid[0.1:0.3:np.complex64(3j)] ) # Related to #16945 grid64_a = mgrid[0.1:0.3:3.3j] grid64_b = mgrid[0.1:0.3:3.3j, ][0] assert_(grid64_a.dtype == grid64_b.dtype == np.float64) assert_array_equal(grid64_a, grid64_b) grid128_a = mgrid[0.1:0.3:np.clongdouble(3.3j)] grid128_b = mgrid[0.1:0.3:np.clongdouble(3.3j), ][0] assert_(grid128_a.dtype == grid128_b.dtype == np.longdouble) assert_array_equal(grid64_a, grid64_b) class TestConcatenator: def test_1d(self): assert_array_equal(r_[1, 2, 3, 4, 5, 6], np.array([1, 2, 3, 4, 5, 6])) b = np.ones(5) c = r_[b, 0, 0, b] assert_array_equal(c, [1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1]) def test_mixed_type(self): g = r_[10.1, 1:10] assert_(g.dtype == 'f8') def test_more_mixed_type(self): g = r_[-10.1, np.array([1]), np.array([2, 3, 4]), 10.0] assert_(g.dtype == 'f8') def test_complex_step(self): # Regression test for #12262 g = r_[0:36:100j] assert_(g.shape == (100,)) # Related to #16466 g = r_[0:36:np.complex64(100j)] assert_(g.shape == (100,)) def test_2d(self): b = np.random.rand(5, 5) c = np.random.rand(5, 5) d = r_['1', b, c] # append columns assert_(d.shape == (5, 10)) assert_array_equal(d[:, :5], b) assert_array_equal(d[:, 5:], c) d = r_[b, c] assert_(d.shape == (10, 5)) assert_array_equal(d[:5, :], b) assert_array_equal(d[5:, :], c) def test_0d(self): assert_equal(r_[0, np.array(1), 2], [0, 1, 2]) assert_equal(r_[[0, 1, 2], np.array(3)], [0, 1, 2, 3]) assert_equal(r_[np.array(0), [1, 2, 3]], [0, 1, 2, 3]) class TestNdenumerate: def test_basic(self): a = np.array([[1, 2], [3, 4]]) assert_equal(list(ndenumerate(a)), [((0, 0), 1), ((0, 1), 2), ((1, 0), 3), ((1, 1), 4)]) class TestIndexExpression: def test_regression_1(self): # ticket #1196 a = np.arange(2) assert_equal(a[:-1], a[s_[:-1]]) assert_equal(a[:-1], a[index_exp[:-1]]) def test_simple_1(self): a = np.random.rand(4, 5, 6) assert_equal(a[:, :3, [1, 2]], a[index_exp[:, :3, [1, 2]]]) assert_equal(a[:, :3, [1, 2]], a[s_[:, :3, [1, 2]]]) class TestIx_: def test_regression_1(self): # Test empty untyped inputs create outputs of indexing type, gh-5804 a, = np.ix_(range(0)) assert_equal(a.dtype, np.intp) a, = np.ix_([]) assert_equal(a.dtype, np.intp) # but if the type is specified, don't change it a, = np.ix_(np.array([], dtype=np.float32)) assert_equal(a.dtype, np.float32) def test_shape_and_dtype(self): sizes = (4, 5, 3, 2) # Test both lists and arrays for func in (range, np.arange): arrays = np.ix_(*[func(sz) for sz in sizes]) for k, (a, sz) in enumerate(zip(arrays, sizes)): assert_equal(a.shape[k], sz) assert_(all(sh == 1 for j, sh in enumerate(a.shape) if j != k)) assert_(np.issubdtype(a.dtype, np.integer)) def test_bool(self): bool_a = [True, False, True, True] int_a, = np.nonzero(bool_a) assert_equal(np.ix_(bool_a)[0], int_a) def test_1d_only(self): idx2d = [[1, 2, 3], [4, 5, 6]] assert_raises(ValueError, np.ix_, idx2d) def test_repeated_input(self): length_of_vector = 5 x = np.arange(length_of_vector) out = ix_(x, x) assert_equal(out[0].shape, (length_of_vector, 1)) assert_equal(out[1].shape, (1, length_of_vector)) # check that input shape is not modified assert_equal(x.shape, (length_of_vector,)) def test_c_(): a = np.c_[np.array([[1, 2, 3]]), 0, 0, np.array([[4, 5, 6]])] assert_equal(a, [[1, 2, 3, 0, 0, 4, 5, 6]]) class TestFillDiagonal: def test_basic(self): a = np.zeros((3, 3), int) fill_diagonal(a, 5) assert_array_equal( a, np.array([[5, 0, 0], [0, 5, 0], [0, 0, 5]]) ) def test_tall_matrix(self): a = np.zeros((10, 3), int) fill_diagonal(a, 5) assert_array_equal( a, np.array([[5, 0, 0], [0, 5, 0], [0, 0, 5], [0, 0, 0], [0, 0, 0], [0, 0, 0], [0, 0, 0], [0, 0, 0], [0, 0, 0], [0, 0, 0]]) ) def test_tall_matrix_wrap(self): a = np.zeros((10, 3), int) fill_diagonal(a, 5, True) assert_array_equal( a, np.array([[5, 0, 0], [0, 5, 0], [0, 0, 5], [0, 0, 0], [5, 0, 0], [0, 5, 0], [0, 0, 5], [0, 0, 0], [5, 0, 0], [0, 5, 0]]) ) def test_wide_matrix(self): a = np.zeros((3, 10), int) fill_diagonal(a, 5) assert_array_equal( a, np.array([[5, 0, 0, 0, 0, 0, 0, 0, 0, 0], [0, 5, 0, 0, 0, 0, 0, 0, 0, 0], [0, 0, 5, 0, 0, 0, 0, 0, 0, 0]]) ) def test_operate_4d_array(self): a = np.zeros((3, 3, 3, 3), int) fill_diagonal(a, 4) i = np.array([0, 1, 2]) assert_equal(np.where(a != 0), (i, i, i, i)) def test_low_dim_handling(self): # raise error with low dimensionality a = np.zeros(3, int) with assert_raises_regex(ValueError, "at least 2-d"): fill_diagonal(a, 5) def test_hetero_shape_handling(self): # raise error with high dimensionality and # shape mismatch a = np.zeros((3,3,7,3), int) with assert_raises_regex(ValueError, "equal length"): fill_diagonal(a, 2) def test_diag_indices(): di = diag_indices(4) a = np.array([[1, 2, 3, 4], [5, 6, 7, 8], [9, 10, 11, 12], [13, 14, 15, 16]]) a[di] = 100 assert_array_equal( a, np.array([[100, 2, 3, 4], [5, 100, 7, 8], [9, 10, 100, 12], [13, 14, 15, 100]]) ) # Now, we create indices to manipulate a 3-d array: d3 = diag_indices(2, 3) # And use it to set the diagonal of a zeros array to 1: a = np.zeros((2, 2, 2), int) a[d3] = 1 assert_array_equal( a, np.array([[[1, 0], [0, 0]], [[0, 0], [0, 1]]]) ) class TestDiagIndicesFrom: def test_diag_indices_from(self): x = np.random.random((4, 4)) r, c = diag_indices_from(x) assert_array_equal(r, np.arange(4)) assert_array_equal(c, np.arange(4)) def test_error_small_input(self): x = np.ones(7) with assert_raises_regex(ValueError, "at least 2-d"): diag_indices_from(x) def test_error_shape_mismatch(self): x = np.zeros((3, 3, 2, 3), int) with assert_raises_regex(ValueError, "equal length"): diag_indices_from(x) def test_ndindex(): x = list(ndindex(1, 2, 3)) expected = [ix for ix, e in ndenumerate(np.zeros((1, 2, 3)))] assert_array_equal(x, expected) x = list(ndindex((1, 2, 3))) assert_array_equal(x, expected) # Test use of scalars and tuples x = list(ndindex((3,))) assert_array_equal(x, list(ndindex(3))) # Make sure size argument is optional x = list(ndindex()) assert_equal(x, [()]) x = list(ndindex(())) assert_equal(x, [()]) # Make sure 0-sized ndindex works correctly x = list(ndindex(*[0])) assert_equal(x, [])