Returns a copy of arr1 that may be non-contiguous or unaligned, and a matching array for arr2 (although not a copy).
(self, arr1, arr2, aligned=True, contig=True)
| 196 | return arr1, arr2, values |
| 197 | |
| 198 | def get_data_variation(self, arr1, arr2, aligned=True, contig=True): |
| 199 | """ |
| 200 | Returns a copy of arr1 that may be non-contiguous or unaligned, and a |
| 201 | matching array for arr2 (although not a copy). |
| 202 | """ |
| 203 | if contig: |
| 204 | stride1 = arr1.dtype.itemsize |
| 205 | stride2 = arr2.dtype.itemsize |
| 206 | elif aligned: |
| 207 | stride1 = 2 * arr1.dtype.itemsize |
| 208 | stride2 = 2 * arr2.dtype.itemsize |
| 209 | else: |
| 210 | stride1 = arr1.dtype.itemsize + 1 |
| 211 | stride2 = arr2.dtype.itemsize + 1 |
| 212 | |
| 213 | max_size1 = len(arr1) * 3 * arr1.dtype.itemsize + 1 |
| 214 | max_size2 = len(arr2) * 3 * arr2.dtype.itemsize + 1 |
| 215 | from_bytes = np.zeros(max_size1, dtype=np.uint8) |
| 216 | to_bytes = np.zeros(max_size2, dtype=np.uint8) |
| 217 | |
| 218 | # Sanity check that the above is large enough: |
| 219 | assert stride1 * len(arr1) <= from_bytes.nbytes |
| 220 | assert stride2 * len(arr2) <= to_bytes.nbytes |
| 221 | |
| 222 | if aligned: |
| 223 | new1 = as_strided(from_bytes[:-1].view(arr1.dtype), |
| 224 | arr1.shape, (stride1,)) |
| 225 | new2 = as_strided(to_bytes[:-1].view(arr2.dtype), |
| 226 | arr2.shape, (stride2,)) |
| 227 | else: |
| 228 | new1 = as_strided(from_bytes[1:].view(arr1.dtype), |
| 229 | arr1.shape, (stride1,)) |
| 230 | new2 = as_strided(to_bytes[1:].view(arr2.dtype), |
| 231 | arr2.shape, (stride2,)) |
| 232 | |
| 233 | new1[...] = arr1 |
| 234 | |
| 235 | if not contig: |
| 236 | # Ensure we did not overwrite bytes that should not be written: |
| 237 | offset = arr1.dtype.itemsize if aligned else 0 |
| 238 | buf = from_bytes[offset::stride1].tobytes() |
| 239 | assert buf.count(b"\0") == len(buf) |
| 240 | |
| 241 | if contig: |
| 242 | assert new1.flags.c_contiguous |
| 243 | assert new2.flags.c_contiguous |
| 244 | else: |
| 245 | assert not new1.flags.c_contiguous |
| 246 | assert not new2.flags.c_contiguous |
| 247 | |
| 248 | if aligned: |
| 249 | assert new1.flags.aligned |
| 250 | assert new2.flags.aligned |
| 251 | else: |
| 252 | assert not new1.flags.aligned or new1.dtype.alignment == 1 |
| 253 | assert not new2.flags.aligned or new2.dtype.alignment == 1 |
| 254 | |
| 255 | return new1, new2 |
no test coverage detected