FORTRAN Reference Manual

Intrinsic Functions
FORTRAN Reference Manual—528615-001
8-8
ASIN Function
ASIN Function
The ASIN function returns an arcsine expressed in radians.
The table below shows the argument and function type for the generic ASIN function
and its associated specific function.
Considerations
•
The result type of the ASIN function is the same as the type of its argument.
•
The value of ASIN (x), where ABS (x) < 1.0, is the angle a (in radians) such that
and x = SIN (a)
•
If ABS (x) > 1.0, program execution terminates abnormally with an error message.
Example of the ASIN Function
The value .602859 is stored in Y:
y = ASIN (.567)
ATAN Function
The ATAN function returns an arctangent expressed in radians.
The table below shows the argument and function type for the ATAN generic function
and its associated specific function.
Syntax Argument Type Function Type
ASIN (x)
ASIN (x)Real Real
DASIN (x) Double Precision Double Precision
x is an arithmetic expression.
Syntax Argument Type Function Type
ATAN (x)
ATAN (x) Real Real
DATAN (x) Double Precision Double Precision
x is an arithmetic expression.
π 2⁄ a π 2⁄≤≤–