ATAN2D (The GNU Fortran Compiler) (original) (raw)
8.26 ATAN2D — Arctangent function, degrees ¶
Synopsis:
RESULT = ATAN2D(Y, X)
Description:
ATAN2D(Y, X) computes the principal value of the argument function of the complex number X + i Y in degrees. This function can be used to transform from Cartesian into polar coordinates and allows to determine the angle in the correct quadrant.
Class:
Elemental function
Arguments:
| Y | The type shall be REAL. |
|---|---|
| X | The type and kind type parameter shall be the same as Y. If Y is zero, then X must be nonzero. |
Return value:
The return value has the same type and kind type parameter as Y. It is the principal value of the complex number X + i Y. If Xis nonzero, then it lies in the range -180 \le \atan (x) \leq 180. The sign is positive if Y is positive. If Y is zero, then the return value is zero if X is strictly positive, 180 ifX is negative and Y is positive zero (or the processor does not handle signed zeros), and -180 if X is negative andY is negative zero. Finally, if X is zero, then the magnitude of the result is 90.
Example:
program test_atan2d real(4) :: x = 1.e0_4, y = 0.5e0_4 x = atan2d(y,x) end program test_atan2d
Specific names:
| Name | Argument | Return type | Standard |
|---|---|---|---|
| ATAN2D(X, Y) | REAL(4) X, Y | REAL(4) | Fortran 2023 |
| DATAN2D(X, Y) | REAL(8) X, Y | REAL(8) | GNU extension |
Standard:
Fortran 2023
See also:
Alias:
ATAND — Arctangent function, degrees
Radians function:
ATAN2 — Arctangent function