intmin_c |

Table of contents## Procedureintmin_c ( Smallest integer number ) SpiceInt intmin_c () ## AbstractReturn the value of the smallest (negative) number representable in a SpiceInt variable. ## Required_ReadingNone. ## KeywordsCONSTANTS ## Brief_I/OThe function returns the value of the smallest (negative) number that can be represented in a SpiceInt variable. ## Detailed_InputNone. ## Detailed_OutputThe 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. ## ParametersNone. ## ExceptionsError free. ## FilesNone. ## ParticularsThe 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. ## ExamplesThe numerical results shown for this example may differ across platforms. The results depend on the SPICE kernels used as input, the compiler and supporting libraries, and the machine specific arithmetic implementation. 1) Obtain the integer part of a double precision number. If the integer component of the number is out of range, avoid overflow by making it as large or small as possible. Example code begins here. /. Program intmin_ex1 ./ #include <stdio.h> #include "SpiceUsr.h" int main( ) { /. Local variables ./ SpiceInt i; SpiceInt ivalue; /. Define a set of three numbers, two of them having an integer component that is out of range. ./ SpiceDouble number [3] = { 2.e40, -1.5e35, 1.6 }; for ( i = 0; i < 3; i++ ) { printf( "Double precision number: %e\n", number[i] ); /. If the integer component is out of range, avoid overflow by making it as large as possible. ./ if ( number[i] > (SpiceDouble)( intmax_c() ) ) { printf( " Overflow! Greater than intmax_c.\n" ); ivalue = intmax_c(); } else if ( number[i] < (SpiceDouble)( ## RestrictionsNone. ## Literature_ReferencesNone. ## Author_and_InstitutionN.J. Bachman (JPL) J. Diaz del Rio (ODC Space) ## Version-CSPICE Version 1.0.1, 10-AUG-2021 (JDR) Edited the header to comply with NAIF standard. Added complete code example from existing code fragment. -CSPICE Version 1.0.0, 29-JAN-1999 (NJB) ## Index_Entriessmallest integer number |

Fri Dec 31 18:41:08 2021