Rotate an array by 90 degrees in the plane specified by axes. Rotation direction is from the first towards the second axis. This means for a 2D array with the default `k` and `axes`, the rotation will be counterclockwise. Parameters ---------- m : array_like Ar
(m, k=1, axes=(0, 1))
| 157 | |
| 158 | @array_function_dispatch(_rot90_dispatcher) |
| 159 | def rot90(m, k=1, axes=(0, 1)): |
| 160 | """ |
| 161 | Rotate an array by 90 degrees in the plane specified by axes. |
| 162 | |
| 163 | Rotation direction is from the first towards the second axis. |
| 164 | This means for a 2D array with the default `k` and `axes`, the |
| 165 | rotation will be counterclockwise. |
| 166 | |
| 167 | Parameters |
| 168 | ---------- |
| 169 | m : array_like |
| 170 | Array of two or more dimensions. |
| 171 | k : integer |
| 172 | Number of times the array is rotated by 90 degrees. |
| 173 | axes : (2,) array_like |
| 174 | The array is rotated in the plane defined by the axes. |
| 175 | Axes must be different. |
| 176 | |
| 177 | .. versionadded:: 1.12.0 |
| 178 | |
| 179 | Returns |
| 180 | ------- |
| 181 | y : ndarray |
| 182 | A rotated view of `m`. |
| 183 | |
| 184 | See Also |
| 185 | -------- |
| 186 | flip : Reverse the order of elements in an array along the given axis. |
| 187 | fliplr : Flip an array horizontally. |
| 188 | flipud : Flip an array vertically. |
| 189 | |
| 190 | Notes |
| 191 | ----- |
| 192 | ``rot90(m, k=1, axes=(1,0))`` is the reverse of |
| 193 | ``rot90(m, k=1, axes=(0,1))`` |
| 194 | |
| 195 | ``rot90(m, k=1, axes=(1,0))`` is equivalent to |
| 196 | ``rot90(m, k=-1, axes=(0,1))`` |
| 197 | |
| 198 | Examples |
| 199 | -------- |
| 200 | >>> m = np.array([[1,2],[3,4]], int) |
| 201 | >>> m |
| 202 | array([[1, 2], |
| 203 | [3, 4]]) |
| 204 | >>> np.rot90(m) |
| 205 | array([[2, 4], |
| 206 | [1, 3]]) |
| 207 | >>> np.rot90(m, 2) |
| 208 | array([[4, 3], |
| 209 | [2, 1]]) |
| 210 | >>> m = np.arange(8).reshape((2,2,2)) |
| 211 | >>> np.rot90(m, 1, (1,2)) |
| 212 | array([[[1, 3], |
| 213 | [0, 2]], |
| 214 | [[5, 7], |
| 215 | [4, 6]]]) |
| 216 |