Procedure

   dpmin_c ( Smallest DP number ) 

   SpiceDouble dpmin_c ()

Abstract

   Return the value of the smallest (negative) number representable
   in a double precision variable.

Required_Reading

   None.

Keywords

   CONSTANTS

Brief_I/O

   The function returns the value of the smallest (negative) number
   that can be represented in a double precision variable.

Detailed_Input

   None.

Detailed_Output

   The function returns the value of the smallest (negative) number
   that can be represented in a double precision variable.

   This value varies from machine to machine. Usually, the value is
   defined as the negative of the macro DBL_MAX from the ANSI standard
   header file float.h. According to the ANSI standard, DBL_MAX must be
   at least

      1.E+37

   Therefore dpmin_c usually returns a value less than or equal to

     -1.E+37

   Exceptional systems would be those where DBL_MAX cannot be negated.
   Currently no such systems are supported.

Parameters

   None.

Exceptions

   Error free.

Files

   None.

Particulars

   The function always returns a constant value, set by the user
   prior to compilation.

Examples

   The following code fragments illustrate the use of dpmin_c.
   Note in the example that the smallest negative number is not assumed
   to be the negative of the largest positive number.

   1) Initialize a CSPICE "window."

      /.
      The window originally has one interval, from "minus
      infinity" to "plus infinity".
      ./

      winsiz    =  2;
      window[0] =  dpmin_c();
      window[1] =  dpmax_c() ;

      scardd_ ( &winsiz, window );

Restrictions

   None.

Literature_References

   None.

Author_and_Institution

   N.J. Bachman        (JPL)
   J. Diaz del Rio     (ODC Space)
   H.A. Neilan         (JPL)
   M.J. Spencer        (JPL)
   W.L. Taber          (JPL)
   I.M. Underwood      (JPL)

Version

   -CSPICE Version 1.0.1, 02-JUN-2021 (JDR)

       Edited the header to comply with NAIF standard.

   -CSPICE Version 1.0.0, 19-OCT-1998 (NJB) (HAN) (MJS) (WLT) (IMU)

Index_Entries

   smallest d.p. number

Link to routine dpmin_c source file dpmin_c.c