Compiler Library/XL Reference Manual (32650-90029)

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Declaration
FUNCTION DSUB(VAR d1,d2:INTEGER):INTEGER; EXTERNAL;
Attributes
Parameters: An integer number.
Result: An integer number.
HP FORTRAN 77/XL: Callable as a system intrinsic: I = DSUB(J,K)
Error: If traps are enabled and if the result cannot
be represented by an integer, the arithmetic
trap INTEGER OVERFLOW occurs.
DTAN (or DTAN')
DTAN calculates the tangent of a longreal number in radians.
Declaration
FUNCTION DTAN(VAR x:LONGREAL):LONGREAL; EXTERNAL;
Accuracy
Attributes
Parameter: A longreal number in radians.
Result: A longreal number.
HP FORTRAN 77/XL: Intrinsic function: Y=DTAN(X).
Error: If the argument is a NaN, there are two
possible actions. If the INVALID trap is
enabled, the message "DTAN(X): X=NaN" occurs.
Otherwise, the INVALID flag is set. In either
case, a quiet NaN is returned.
When DABS(X) > 149078413.0, DTAN(X) completely
loses significance. See Appendix A for more
details.
DTANH (or DTANH')
DTANH calculates the hyperbolic tangent of a longreal number.
Declaration
FUNCTION DTANH(VAR x:LONGREAL):LONGREAL; EXTERNAL;
Accuracy
When x-y ~ , maximum f-g ~ sec
2
x