HP OpenVMS RTL Library (LIB$) Manual
The maximum representable floatingpoint values (max_float) for the
IEEE_S_Floating, IEEE_T_Floating, IEEE_X_Floating,
Big_Endian_IEEE_S_Floating, Big_Endian_IEEE_T_Floating, and
Big_Endian_IEEE_X_Floating formats are:
Data Type 
Value for: max_float 
S

Decimal: 3.402823e38

T

Decimal: 1.797693134862316e308

X

Decimal: 1.189731495357231765085759326628007016196477e4932

Declarations for the options argument are in the $CVTDEF module found
in the system symbol libraries.
Description
CVT$FTOF functionality is available on all HP platforms and is the
floatingpoint conversion routine of choice for portability. When
compared with the standard CVT$CONVERT_FLOAT routine, CVT$FTOF includes
additional functionality and increased performance.
CVT$FTOF is a generalpurpose floatingpoint conversion routine that
converts any input_type_code floatingpoint data type
into any output_type_code floatingpoint data type.
The conversion is subject to the options specified in the
options argument.
Note
OpenVMS compilers do not support arithmetic operations for all of the
floatingpoint data types described here. Additional floatingpoint
data types are supported by this routine for data conversion purposes
only.

