diff options
Diffstat (limited to 'numpy/lib/index_tricks.py')
| -rw-r--r-- | numpy/lib/index_tricks.py | 23 |
1 files changed, 20 insertions, 3 deletions
diff --git a/numpy/lib/index_tricks.py b/numpy/lib/index_tricks.py index 8d4b1ce1e..40c1cda05 100644 --- a/numpy/lib/index_tricks.py +++ b/numpy/lib/index_tricks.py @@ -813,7 +813,7 @@ def fill_diagonal(a, val, wrap=False): The wrap option affects only tall matrices: >>> # tall matrices no wrap - >>> a = np.zeros((5, 3),int) + >>> a = np.zeros((5, 3), int) >>> np.fill_diagonal(a, 4) >>> a array([[4, 0, 0], @@ -823,7 +823,7 @@ def fill_diagonal(a, val, wrap=False): [0, 0, 0]]) >>> # tall matrices wrap - >>> a = np.zeros((5, 3),int) + >>> a = np.zeros((5, 3), int) >>> np.fill_diagonal(a, 4, wrap=True) >>> a array([[4, 0, 0], @@ -833,13 +833,30 @@ def fill_diagonal(a, val, wrap=False): [4, 0, 0]]) >>> # wide matrices - >>> a = np.zeros((3, 5),int) + >>> a = np.zeros((3, 5), int) >>> np.fill_diagonal(a, 4, wrap=True) >>> a array([[4, 0, 0, 0, 0], [0, 4, 0, 0, 0], [0, 0, 4, 0, 0]]) + The anti-diagonal can be filled by reversing the order of elements + using either `numpy.flipud` or `numpy.fliplr`. + + >>> a = np.zeros((3, 3), int); + >>> np.fill_diagonal(np.fliplr(a), [1,2,3]) # Horizontal flip + >>> a + array([[0, 0, 1], + [0, 2, 0], + [3, 0, 0]]) + >>> np.fill_diagonal(np.flipud(a), [1,2,3]) # Vertical flip + >>> a + array([[0, 0, 3], + [0, 2, 0], + [1, 0, 0]]) + + Note that the order in which the diagonal is filled varies depending + on the flip function. """ if a.ndim < 2: raise ValueError("array must be at least 2-d") |