TOMS722
IEEE Arithmetic Support

TOMS722 is a C library which supports IEEE arithmetic. Both single and double precision routines are supplied.

Compilation of the functions requires specifying a compiler flag that indicates whether big-endian or little-endian storage is used, and whether graceful underflow occurs.

The current results used the compiler flag "-DBEG", but there are four pairs of computations that had to be commented out in order for the tests to run.

The original, correct and authentic copies of the source code are available from the TOMS subdirectory of NETLIB.

Licensing:

The computer code and data files described and made available on this web page are distributed under the GNU LGPL license.

Languages:

TOMS722 is available in a C version.

Related Data and Programs:

MACHAR, a C library which can compute machine arithmetic quantities dynamically.

MACHINE, a C library which stores the appropriate values of machine constants for a given machine.

Reference:

1. William Cody, Jerome Coonen,
   Algorithm 722: Functions to support the IEEE standard for binary floating point arithmetic;
   ACM Transactions on Mathematical Software,
   Volume 19, Number 4, December 1993, pages 443-451.

Source Code:

• toms722.c, the source code;
• toms722.h, the INCLUDE file;

Examples and Tests:

• toms722_test.c, the calling program;
• toms722_test.txt, the output file.

List of Routines:

• COPYSIGN_D returns the first argument with the sign of the second.
• COPYSIGN_F returns the first argument with the sign of the second.
• FINITE_D returns true (1) if its argument is finite, and false (0) otherwise.
• FINITE_F returns true (1) if its argument is finite, and false (0) otherwise.
• ISNAN_D returns true (1) if its argument is NaN, and false (0) otherwise.
• ISNAN_F returns true (1) if its argument is NaN, and false (0) otherwise.
• LOGB_D returns the exponent of a real number.
• LOGB_F returns the exponent of a real number.
• MACHAR_D computes machine constants for double floating point arithmetic.
• MACHAR_S computes machine constants for floating point arithmetic.
• NEXTAFTER_D returns the next value in a given direction.
• NEXTAFTER_F returns the next value in a given direction.
• SCALB_D returns ARG * 2 ^ N.
• SCALB_F returns ARG * 2 ^ N.
• TEST_D returns its input argument.
• TEST_F returns its input argument.
• TIMESTAMP prints the current YMDHMS date as a time stamp.

You can go up one level to the C source codes.