Next: DEC Alpha 3000 Up: VAXStation 3100 (cvsa3) Previous: C Version

FORTRAN Version


Diagnosis resumes after milestone  #    7,    ... page     5

Program is now RUNNING tests on small integers:
-1, 0, 1/2 , 1, 2, 3, 4, 5, 9, 27, 32 & 240 are O.K.

Searching for radix and precision...
Radix =   2.
Closest relative separation found is   1.38777878E-17
Recalculating radix and precision 
confirms closest relative separation .
Radix confirmed.
The number of significant digits of radix   2. is  56.00
Test for extra-precise subexpressions:
Subexpressions do not appear to be calculated
 with extra precision.

To continue diagnosis, press return.

Diagnosis resumes after milestone  #   30,    ... page     6

Subtraction appears to be normalized as it should.
Checking for guard digits in multiply divide and subtract.
These operations appear to have guard digits as they should.

To continue diagnosis, press return.

Diagnosis resumes after milestone  #   40,    ... page     7

Checking for rounding in multiply, divide and add/subtract:
Multiplication appears to be correctly rounded.
Division appears to be correctly rounded.
Add/subtract appears to be correctly rounded.
checking for sticky bit:
Sticky bit used incorrectly or not at all.

Does multiplication commute? Testing if  x*y = y*x  for  20 random pairs:
No failure found in   20 randomly chosen pairs.

Running tests of square root...
Testing if  sqrt(x*x)  =  x  for    20 integers  x.
Found no discrepancies.
Sqrt has passed a test for monotonicity.
Testing whether  sqrt  is rounded or chopped:
Square root appears to be correctly rounded.

To continue diagnosis, press return.

Diagnosis resumes after milestone  #   90,    ... page     8

Testing powers  z^i  for small integers  z  and  i :
Start with 0.**0 .
%MTH-F-UNDEXP, undefined exponentiation
  user PC 00005EEA
%TRACE-F-TRACEBACK, symbolic stack dump follows
module name     routine name                     line       rel PC    abs PC

                                                           0000CD28  0000CD28
                                                           0003300B  0003300B
PWRCMP          PWRCMP                             32      0000001A  00005EEA
POWER           POWER                              57      0000008B  00006D83
DPARA$MAIN      DPARA$MAIN                        257      000004B2  00004CB2

CVSA3_CBU.PARANOIA> run dpara
Is this a program restart after failure (1)
or a start from scratch (0) ?
1
Restarting from milestone    90.

To continue diagnosis, press return.

Diagnosis resumes after milestone  #   90,    ... page     9

Testing powers  z^i  for small integers  z  and  i :
No discrepancies found.

Seeking underflow threshold and min positive number:
Smallest strictly positive number found is  minpos  =  2.93873588E-39
Since comparison denies   MINPOS  = 0,
 evaluating  ( MINPOS  +  MINPOS ) /  MINPOS   should be safe;
what the machine gets for  ( MINPOS  +  MINPOS ) /  MINPOS   is
           0.2000000E+01
This is O.K. provided over/underflow has not just been signaled.
FLAW:  x =  0.40407618E-38 is unequal to  z =  0.29387359E-38 ,
yet  x-z  yields   0.0000000E+00
Should this not signal underflow, this is a SERIOUS
DEFECT that causes confusion when innocent statements like
if (x.eq.z) then ... else ... ( f(x)-f(z) )/(x-z) ...
encounter division by zero although actually  x/z = 1 +   0.37500000E+00
The  underflow threshold is   0.29387359E-38 , below which
calculation may suffer larger relative error than merely roundoff.
SERIOUS 
DEFECT:  range is too narrow;   ulpmin^    4  underflows.

To continue diagnosis, press return.

Diagnosis resumes after milestone  #  130,    ... page    10

since underflow occurs below the threshold  =
         (  2.00000000E+00)^( -1.28000000E+02) ,
only underflow should afflict the expression
         (  2.00000000E+00)^( -2.56000000E+02) ;
actually calculating it yields   
  0.00000000E+00
This computed value is O.K.
Testing  x^((x+1)/(x-1)) vs. exp(2) =   0.73890561E+01  as  x-> 1.
Accuracy seems adequate.
Testing powers  z^q  at four nearly extreme values:
No discrepancies found.


To continue diagnosis, press return.

Diagnosis resumes after milestone  #  160,    ... page    11

Searching for overflow threshold:
%SYSTEM-F-FLTOVF_F, arithmetic fault, floating overflow at PC=00006244, PSL=03C0
0020
%TRACE-F-TRACEBACK, symbolic stack dump follows
module name     routine name                     line       rel PC    abs PC

OVERF           OVERF                             104      0000026C  00006244
DPARA$MAIN      DPARA$MAIN                        276      000004D3  00004CD3

CVSA3_CBU.PARANOIA> run dpara
Is this a program restart after failure (1)
or a start from scratch (0) ?
1
Restarting from milestone   161.
Can " z = -y " overflow?  trying it on  y =  -8.50705917E+37
Seems O.K.
Overflow threshold is  v =   1.70141183E+38
There is no saturation value because
the system traps on overflow.
No overflow should be signaled for  v*1 = 
                                            1.70141183E+38
                           nor for  v/1 = 
                                            1.70141183E+38
Any overflow signal separating this  *  from one above is a DEFECT.

To continue diagnosis, press return.

Diagnosis resumes after milestone  #  190,    ... page    12


What messages and/or values does division by zero produce?
About to compute 1/0...
%SYSTEM-F-FLTDIV_F, arithmetic fault, floating divide by zero at PC=0000A894, PS
L=03C00020
%TRACE-F-TRACEBACK, symbolic stack dump follows
module name     routine name                     line       rel PC    abs PC

ZEROS           ZEROS                              52      00000074  0000A894
DPARA$MAIN      DPARA$MAIN                        282      000004E4  00004CE4

CVSA3_CBU.PARANOIA> run dpara
Is this a program restart after failure (1)
or a start from scratch (0) ?
1
Restarting from milestone   211.
About to compute 0/0...
%SYSTEM-F-FLTDIV_F, arithmetic fault, floating divide by zero at PC=0000A8F0, PS
L=03C00020
%TRACE-F-TRACEBACK, symbolic stack dump follows
module name     routine name                     line       rel PC    abs PC

ZEROS           ZEROS                              59      000000D0  0000A8F0
DPARA$MAIN      DPARA$MAIN                        282      000004E4  00004CE4

CVSA3_CBU.PARANOIA> run dpara
Is this a program restart after failure (1)
or a start from scratch (0) ?
1
Restarting from milestone   212.

To continue diagnosis, press return.

Diagnosis resumes after milestone  #  220,    ... page    13

The number of  SERIOUS DEFECTs  discovered =    1
The number of  FLAWs  discovered =              1
The arithmetic diagnosed has unacceptable Serious Defects.
End of Test.


peter@physik3.gwdg.de
Tue Aug 8 13:05:00 GMT+0200 1995