ATAN
The ATAN function returns the arc tangent of the argument as an angle expressed in radians. The ATAN and TAN functions are inverse operations.
- expression
- An expression that returns a value of any built-in numeric data type (except for DECFLOAT), character-string, or graphic-string data type. A string argument is cast to double-precision floating point before evaluating the function. For more information about converting strings to double-precision floating point, see DOUBLE_PRECISION or DOUBLE.
The data type of the result is double-precision floating point. If the argument can be null, the result can be null; if the argument is null, the result is the null value.
The result is greater than or equal to -π/2 and less than or equal to π/2.
Example
- Assume the host variable ATANGENT is a DECIMAL(10,8) host variable
with a value of 14.10141995.
Returns the approximate value 1.50.SELECT ATAN(:ATANGENT) FROM SYSIBM.SYSDUMMY1