Developer Guide and Reference

ID 767251
Date 10/31/2024
Public
Document Table of Contents

ATAN2D

Elemental Intrinsic Function (Generic): Produces an arctangent in degrees. The result is the principal value of the argument of the nonzero complex number (x, y).

result = ATAN2D (y,x)

y

(Input) Must be of type real.

x

(Input) Must have the same type and kind parameters as y. If y has the value zero, x cannot have the value zero.

Results

The result type and kind are the same as x and are expressed in degrees. The value lies in the range -180 degrees to 180 degrees. If x zero, the result is approximately equal to the value of arctan (y/ x).

If y > zero, the result is positive.

If y < zero, the result is negative.

If y = zero, the result is zero (if x > zero) or 180 degrees (if x < zero).

If x = zero, the absolute value of the result is 90 degrees.

Specific Name

Argument Type

Result Type

ATAN2D

REAL(4)

REAL(4)

DATAN2D

REAL(8)

REAL(8)

QATAN2D

REAL(16)

REAL(16)

Example

ATAN2D (2.679676, 1.0) has the value 69.53546.