bwBASIC/NBS2/P129.OUT

PROGRAM FILE 129: EXCEPTION - OVERFLOW ON VALUE OF
        TAN FUNCTION.
    ANSI STANDARD 8.5

SECTION 129.1: EXCEPTION - OVERFLOW ON VALUE OF
        TAN FUNCTION.

THE OBJECT OF THIS TEST IS TO SEE WHETHER THE PROCESSOR
RECOGNIZES AN EXCEPTION OF THE VALUE RETURNED BY THE
TAN FUNCTION EXCEEDS MACHINE INFINITY.

TO PASS THIS TEST:

    1) OVERFLOW MUST NOT OCCUR, OR

    2) WHEN OVERFLOW OCCURS, THE PROCESSOR MUST DISPLAY A
       MESSAGE IDENTIFYING THE EXCEPTION, SUPPLY MACHINE
       INFINITY AND CONTINUE EXECUTION.


                               BEGIN TEST.

THE PROGRAM ATTEMPTS TO FORCE CONVERGENCE OF THE ARGUMENT
TO PI/2, SO AS TO CAUSE OVERFLOW. IF OVERFLOW DOES NOT
OCCUR, IT IS LIKELY THAT THIS SYSTEM HAS NO INTERNAL
NUMERIC REPRESENTATION FOR WHICH THE TANGENT EXCEEDS
MACHINE INFINITY.

ARGUMENT       VALUE OF TAN

 1.57           1255.77 
 1.575         -237.886 
 1.5725        -586.966 
 1.57125       -2204.23 
 1.57063        5836.8 
 1.57094       -7083.5 
 1.57078        66327.1 
 1.57086       -15860.9 
 1.57082       -41691.5 
 1.5708        -224494. 
 1.57079        188282. 
 1.5708         2.3345E+6 
 1.5708        -496759. 
 1.5708        -1.26208E+6 
 1.5708        -5.49468E+6 
 1.5708         8.11809E+6 
 1.5708        -3.40063E+7 
 1.5708         2.13276E+7 
 1.5708         1.14407E+8 
 1.5708        -9.67793E+7 
 1.5708        -1.25621E+9 
 1.5708         2.51742E+8 
 1.5708         6.29667E+8 
 1.5708         2.52495E+9 
 1.5708        -5.00002E+9 
 1.5708         1.02016E+10 
 1.5708        -1.96126E+10 
 1.5708         4.25204E+10 
 1.5708        -7.28081E+10 
 1.5708         2.04428E+11 
 1.5708        -2.26167E+11 
 1.5708         4.2556E+12 
 1.5708        -4.77697E+11 
 1.5708        -1.0762E+12 
 1.5708        -2.88005E+12 
 1.5708        -1.78202E+13 
 1.5708         1.11953E+13 
 1.5708         6.06335E+13 
 1.5708        -5.01938E+13 
 1.5708        -5.83048E+14 
 1.5708         1.35342E+14 
 1.5708         3.66869E+14 
 1.5708         1.97894E+15 
 1.5708        -1.65316E+15 
 1.5708         1.63312E+16 
 1.5708        -2.61194E+15 
 1.5708        -6.21843E+15 
 1.5708         1.63312E+16 

ARGUMENTS HAVE CONVERGED. IF OVERFLOW HAS OCCURRED,
PROCESSOR MUST HAVE REPORTED EXCEPTION AND SUPPLIED
MACHINE INFINITY, OTHERWISE,
***  TEST FAILED  ***

                                 END TEST

END PROGRAM 129