root / src / lapack / double / dlaisnan.f @ 2
Historique | Voir | Annoter | Télécharger (1,28 ko)
| 1 | 1 | equemene | LOGICAL FUNCTION DLAISNAN( DIN1, DIN2 ) |
|---|---|---|---|
| 2 | 1 | equemene | * |
| 3 | 1 | equemene | * -- LAPACK auxiliary routine (version 3.2.2) -- |
| 4 | 1 | equemene | * -- LAPACK is a software package provided by Univ. of Tennessee, -- |
| 5 | 1 | equemene | * -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- |
| 6 | 1 | equemene | * June 2010 |
| 7 | 1 | equemene | * |
| 8 | 1 | equemene | * .. Scalar Arguments .. |
| 9 | 1 | equemene | DOUBLE PRECISION DIN1, DIN2 |
| 10 | 1 | equemene | * .. |
| 11 | 1 | equemene | * |
| 12 | 1 | equemene | * Purpose |
| 13 | 1 | equemene | * ======= |
| 14 | 1 | equemene | * |
| 15 | 1 | equemene | * This routine is not for general use. It exists solely to avoid |
| 16 | 1 | equemene | * over-optimization in DISNAN. |
| 17 | 1 | equemene | * |
| 18 | 1 | equemene | * DLAISNAN checks for NaNs by comparing its two arguments for |
| 19 | 1 | equemene | * inequality. NaN is the only floating-point value where NaN != NaN |
| 20 | 1 | equemene | * returns .TRUE. To check for NaNs, pass the same variable as both |
| 21 | 1 | equemene | * arguments. |
| 22 | 1 | equemene | * |
| 23 | 1 | equemene | * A compiler must assume that the two arguments are |
| 24 | 1 | equemene | * not the same variable, and the test will not be optimized away. |
| 25 | 1 | equemene | * Interprocedural or whole-program optimization may delete this |
| 26 | 1 | equemene | * test. The ISNAN functions will be replaced by the correct |
| 27 | 1 | equemene | * Fortran 03 intrinsic once the intrinsic is widely available. |
| 28 | 1 | equemene | * |
| 29 | 1 | equemene | * Arguments |
| 30 | 1 | equemene | * ========= |
| 31 | 1 | equemene | * |
| 32 | 1 | equemene | * DIN1 (input) DOUBLE PRECISION |
| 33 | 1 | equemene | * |
| 34 | 1 | equemene | * DIN2 (input) DOUBLE PRECISION |
| 35 | 1 | equemene | * Two numbers to compare for inequality. |
| 36 | 1 | equemene | * |
| 37 | 1 | equemene | * ===================================================================== |
| 38 | 1 | equemene | * |
| 39 | 1 | equemene | * .. Executable Statements .. |
| 40 | 1 | equemene | DLAISNAN = (DIN1.NE.DIN2) |
| 41 | 1 | equemene | RETURN |
| 42 | 1 | equemene | END |