SpiceInt intmin_c ()
Return the value of the smallest (negative) number representable
in a SpiceInt variable.
None.
CONSTANTS
The function returns the value of the smallest (negative) number
that can be represented in a SpiceInt variable.
None.
The function returns the value of the smallest (negative) number
that can be represented in an SpiceInt variable, where SpiceInt
is a typedef defined in SpiceZdf.h.
The returned value will be less than or equal to -2147483647.
See the Particulars section for details.
None.
Error free.
None.
The typedef SpiceInt is used throughout the CSPICE API to refer to
integers; the precise type of integer is platform-dependent. A
SpiceInt always maps to the same type as does the f2c typedef
integer.
When translating Fortran code, f2c maps Fortran variables of type
INTEGER to C variables of type "integer," where integer is a typedef
defined in the f2c header file f2c.h. On all supported platforms,
Fortran INTEGERS occupy at least 32 bits. On most platforms, this
means that the typedef integer translates to type long. There are
some exceptional platforms on which an integer translates to type
int. The mapping must provide compatibility with the f2c typedef
doublereal: integers must occupy half the storage of doublereals in
order for these types to correctly represent the Fortran types
INTEGER and DOUBLE PRECISION.
On systems where the typedef integer maps to type long, the return
value is defined by the macro LONG_MIN from the ANSI standard header
file limits.h. According to the ANSI standard, LONG_MIN must be no
greater than
-2147483647
This is
31
- ( 2 - 1 )
On systems where the typedef integer maps to type int, the value is
defined by the macro INT_MIN from the ANSI standard header file
limits.h. According to the ANSI standard, INT_MIN must be no greater
than
-32767
This is
15
-( 2 - 1 )
In practice however, the typedef integer will map to type int only
if ints occupy at least four bytes, so the value of INT_MIN will
actually be no greater than -2147483647.
The following code fragment illustrates the use of intmin_c.
/.
Separate a double into integer and fractional components.
If the integer component is out of range, avoid overflow
by making it as large as possible.
./
#include <math.h>
.
.
.
fract = modf ( dvalue, &integralDP );
if ( integralDP > (double)intmax_c() )
{
ivalue = intmax_c();
}
else if ( integralDP < (double)intmin_c() )
{
ivalue = intmin_c();
}
else
{
ivalue = (long)( integralDP );
}
None.
None.
N.J. Bachman (JPL)
W.L. Taber (JPL)
I.M. Underwood (JPL)
-CSPICE Version 1.0.0, 29-JAN-1999 (NJB)
smallest integer number
Link to routine intmin_c source file intmin_c.c
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