| 300 | |
| 301 | @platform_skip |
| 302 | def test_special_values(self): |
| 303 | # C99: Sec G 6.4.2 |
| 304 | |
| 305 | check = check_complex_value |
| 306 | f = np.sqrt |
| 307 | |
| 308 | # csqrt(+-0 + 0i) is 0 + 0i |
| 309 | check(f, np.PZERO, 0, 0, 0) |
| 310 | check(f, np.NZERO, 0, 0, 0) |
| 311 | |
| 312 | # csqrt(x + infi) is inf + infi for any x (including NaN) |
| 313 | check(f, 1, np.inf, np.inf, np.inf) |
| 314 | check(f, -1, np.inf, np.inf, np.inf) |
| 315 | |
| 316 | check(f, np.PZERO, np.inf, np.inf, np.inf) |
| 317 | check(f, np.NZERO, np.inf, np.inf, np.inf) |
| 318 | check(f, np.inf, np.inf, np.inf, np.inf) |
| 319 | check(f, -np.inf, np.inf, np.inf, np.inf) |
| 320 | check(f, -np.nan, np.inf, np.inf, np.inf) |
| 321 | |
| 322 | # csqrt(x + nani) is nan + nani for any finite x |
| 323 | check(f, 1, np.nan, np.nan, np.nan) |
| 324 | check(f, -1, np.nan, np.nan, np.nan) |
| 325 | check(f, 0, np.nan, np.nan, np.nan) |
| 326 | |
| 327 | # csqrt(-inf + yi) is +0 + infi for any finite y > 0 |
| 328 | check(f, -np.inf, 1, np.PZERO, np.inf) |
| 329 | |
| 330 | # csqrt(inf + yi) is +inf + 0i for any finite y > 0 |
| 331 | check(f, np.inf, 1, np.inf, np.PZERO) |
| 332 | |
| 333 | # csqrt(-inf + nani) is nan +- infi (both +i infi are valid) |
| 334 | def _check_ninf_nan(dummy): |
| 335 | msgform = "csqrt(-inf, nan) is (%f, %f), expected (nan, +-inf)" |
| 336 | z = np.sqrt(np.array(complex(-np.inf, np.nan))) |
| 337 | #Fixme: ugly workaround for isinf bug. |
| 338 | with np.errstate(invalid='ignore'): |
| 339 | if not (np.isnan(z.real) and np.isinf(z.imag)): |
| 340 | raise AssertionError(msgform % (z.real, z.imag)) |
| 341 | |
| 342 | _check_ninf_nan(None) |
| 343 | |
| 344 | # csqrt(+inf + nani) is inf + nani |
| 345 | check(f, np.inf, np.nan, np.inf, np.nan) |
| 346 | |
| 347 | # csqrt(nan + yi) is nan + nani for any finite y (infinite handled in x |
| 348 | # + nani) |
| 349 | check(f, np.nan, 0, np.nan, np.nan) |
| 350 | check(f, np.nan, 1, np.nan, np.nan) |
| 351 | check(f, np.nan, np.nan, np.nan, np.nan) |
| 352 | |
| 353 | # XXX: check for conj(csqrt(z)) == csqrt(conj(z)) (need to fix branch |
| 354 | # cuts first) |
| 355 | |
| 356 | class TestCpow: |
| 357 | def setup_method(self): |