Example 1: Character function:
CHARACTER*5 FUNCTION BOOL(ARG) BOOL = 'TRUE' IF (ARG .LE. 0) BOOL = 'FALSE' RETURN END
In the above example, BOOL is defined as a function of type CHARACTER with a length of 5 characters. This function when called returns the string, TRUE or FALSE, depending on the value of the variable, ARG.
FUNCTION SQR (A) SQR = A*A RETURN END
In the above example, the function SQR is defined as function of type REAL by default, and returns the square of the number passed to it.
Example 3: Size of function, alternate syntax: @
INTEGER FUNCTION FCN*2 ( A, B, C )
The above nonstandard form is treated as:
INTEGER*2 FUNCTION FCN ( A, B, C )