(self)
| 435 | @unittest.expectedFailure # TODO: RUSTPYTHON; TypeError: must be real number, not complex |
| 436 | @support.requires_IEEE_754 |
| 437 | def test_float_pow(self): |
| 438 | # test builtin pow and ** operator for IEEE 754 special cases. |
| 439 | # Special cases taken from section F.9.4.4 of the C99 specification |
| 440 | |
| 441 | for pow_op in pow, operator.pow: |
| 442 | # x**NAN is NAN for any x except 1 |
| 443 | self.assertTrue(isnan(pow_op(-INF, NAN))) |
| 444 | self.assertTrue(isnan(pow_op(-2.0, NAN))) |
| 445 | self.assertTrue(isnan(pow_op(-1.0, NAN))) |
| 446 | self.assertTrue(isnan(pow_op(-0.5, NAN))) |
| 447 | self.assertTrue(isnan(pow_op(-0.0, NAN))) |
| 448 | self.assertTrue(isnan(pow_op(0.0, NAN))) |
| 449 | self.assertTrue(isnan(pow_op(0.5, NAN))) |
| 450 | self.assertTrue(isnan(pow_op(2.0, NAN))) |
| 451 | self.assertTrue(isnan(pow_op(INF, NAN))) |
| 452 | self.assertTrue(isnan(pow_op(NAN, NAN))) |
| 453 | |
| 454 | # NAN**y is NAN for any y except +-0 |
| 455 | self.assertTrue(isnan(pow_op(NAN, -INF))) |
| 456 | self.assertTrue(isnan(pow_op(NAN, -2.0))) |
| 457 | self.assertTrue(isnan(pow_op(NAN, -1.0))) |
| 458 | self.assertTrue(isnan(pow_op(NAN, -0.5))) |
| 459 | self.assertTrue(isnan(pow_op(NAN, 0.5))) |
| 460 | self.assertTrue(isnan(pow_op(NAN, 1.0))) |
| 461 | self.assertTrue(isnan(pow_op(NAN, 2.0))) |
| 462 | self.assertTrue(isnan(pow_op(NAN, INF))) |
| 463 | |
| 464 | # (+-0)**y raises ZeroDivisionError for y a negative odd integer |
| 465 | self.assertRaises(ZeroDivisionError, pow_op, -0.0, -1.0) |
| 466 | self.assertRaises(ZeroDivisionError, pow_op, 0.0, -1.0) |
| 467 | |
| 468 | # (+-0)**y raises ZeroDivisionError for y finite and negative |
| 469 | # but not an odd integer |
| 470 | self.assertRaises(ZeroDivisionError, pow_op, -0.0, -2.0) |
| 471 | self.assertRaises(ZeroDivisionError, pow_op, -0.0, -0.5) |
| 472 | self.assertRaises(ZeroDivisionError, pow_op, 0.0, -2.0) |
| 473 | self.assertRaises(ZeroDivisionError, pow_op, 0.0, -0.5) |
| 474 | |
| 475 | # (+-0)**y is +-0 for y a positive odd integer |
| 476 | self.assertEqualAndEqualSign(pow_op(-0.0, 1.0), -0.0) |
| 477 | self.assertEqualAndEqualSign(pow_op(0.0, 1.0), 0.0) |
| 478 | |
| 479 | # (+-0)**y is 0 for y finite and positive but not an odd integer |
| 480 | self.assertEqualAndEqualSign(pow_op(-0.0, 0.5), 0.0) |
| 481 | self.assertEqualAndEqualSign(pow_op(-0.0, 2.0), 0.0) |
| 482 | self.assertEqualAndEqualSign(pow_op(0.0, 0.5), 0.0) |
| 483 | self.assertEqualAndEqualSign(pow_op(0.0, 2.0), 0.0) |
| 484 | |
| 485 | # (-1)**+-inf is 1 |
| 486 | self.assertEqualAndEqualSign(pow_op(-1.0, -INF), 1.0) |
| 487 | self.assertEqualAndEqualSign(pow_op(-1.0, INF), 1.0) |
| 488 | |
| 489 | # 1**y is 1 for any y, even if y is an infinity or nan |
| 490 | self.assertEqualAndEqualSign(pow_op(1.0, -INF), 1.0) |
| 491 | self.assertEqualAndEqualSign(pow_op(1.0, -2.0), 1.0) |
| 492 | self.assertEqualAndEqualSign(pow_op(1.0, -1.0), 1.0) |
| 493 | self.assertEqualAndEqualSign(pow_op(1.0, -0.5), 1.0) |
| 494 | self.assertEqualAndEqualSign(pow_op(1.0, -0.0), 1.0) |
nothing calls this directly
no test coverage detected