PARANOIA
Kahan's Floating Point Test Program

PARANOIA is a C program which tests the floating point arithmetic implementation on a computer.

PARANOIA was originally written in BASIC (!) by Professor William Kahan.

The original, true, correct version of PARANOIA is available in the PARANOIA subdirectory of the NETLIB web site.

Licensing:

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

Languages:

PARANOIA is available in a C version and a FORTRAN90 version.

Related Data and Programs:

MACHAR, a C library which computes the appropriate values of machine constants for a given machine.

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

Reference:

• Richard Karpinski,
  Paranoia: A floating-point benchmark,
  Byte Magazine,
  Volume 10, Number 2, February 1985, pages 223-235.

Source Code:

• paranoia.c, the source code;
• paranoia.sh, commands to compile and load the source code;

Examples and Tests:

• paranoia_input.txt, a file that can be used as the input to PARANOIA.
• paranoia_output_alpha.txt, the output of a run on a Dec ALPHA;
• paranoia_output_osx.txt, the output of a run on Macintosh computer running OSX.

List of Routines:

• PARANOIA tests the floating point arithmetic implementation on a computer.
• SIGFPE is the floating point exception receiver.
• SIGN returns the sign of a floating point value.
• PAUSE pauses program execution until the user hits RETURN.
• TSTCOND checks whether an error has occurred.
• BADCOND tracks and prints the various levels of error.
• RANDOM computes a new random value.
• SQXMINX ???.
• NEWD ???.
• SR3750 ???.
• ISYEQX checks whether two quantities are equal, as they should be.
• SR3980 ???
• PRINTLFNPOSITIVE warns if a discrepancy occurred one or more times.
• TstPtUf???
• NOTIFY warns if a test appears to be inconsistent.
• MSGLIST prints out a block of test.
• INSTRUCTIONS prints some instructions.
• HEADING prints a heading.
• CHARACTERISTICS explains the arithmetic properties to be checked.
• HISTORY prints out an explanation of the program, and history.

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