ATAN(X)
computes the arctangent of X.
Fortran 77 and later, for a complex argument and for two arguments Fortran 2008 or later
Elemental function
RESULT = ATAN(X) |
RESULT = ATAN(Y, X) |
X | The type shall be REAL or COMPLEX ; if Y is present, X shall be REAL. |
Y shall be of the same type and kind as X. |
The return value is of the same type and kind as X. If Y is present, the result is identical to ATAN2(Y,X)
. Otherwise, it the arcus tangent of X, where the real part of the result is in radians and lies in the range -\pi/2 \leq \Re \atan(x) \leq \pi/2.
program test_atan real(8) :: x = 2.866_8 x = atan(x) end program test_atan
Name | Argument | Return type | Standard |
ATAN(X) |
REAL(4) X |
REAL(4) |
Fortran 77 and later |
DATAN(X) |
REAL(8) X |
REAL(8) |
Fortran 77 and later |
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Licensed under the GNU Free Documentation License, Version 1.3.
https://gcc.gnu.org/onlinedocs/gcc-7.2.0/gfortran/ATAN.html