Modules/fpetestmodule.c

   1 /*
   2      ---------------------------------------------------------------------
   3     /                       Copyright (c) 1996.                           \
   4    |          The Regents of the University of California.                 |
   5    |                        All rights reserved.                           |
   6    |                                                                       |
   7    |   Permission to use, copy, modify, and distribute this software for   |
   8    |   any purpose without fee is hereby granted, provided that this en-   |
   9    |   tire notice is included in all copies of any software which is or   |
  10    |   includes  a  copy  or  modification  of  this software and in all   |
  11    |   copies of the supporting documentation for such software.           |
  12    |                                                                       |
  13    |   This  work was produced at the University of California, Lawrence   |
  14    |   Livermore National Laboratory under  contract  no.  W-7405-ENG-48   |
  15    |   between  the  U.S.  Department  of  Energy and The Regents of the   |
  16    |   University of California for the operation of UC LLNL.              |
  17    |                                                                       |
  18    |                              DISCLAIMER                               |
  19    |                                                                       |
  20    |   This  software was prepared as an account of work sponsored by an   |
  21    |   agency of the United States Government. Neither the United States   |
  22    |   Government  nor the University of California nor any of their em-   |
  23    |   ployees, makes any warranty, express or implied, or  assumes  any   |
  24    |   liability  or  responsibility  for the accuracy, completeness, or   |
  25    |   usefulness of any information,  apparatus,  product,  or  process   |
  26    |   disclosed,   or  represents  that  its  use  would  not  infringe   |
  27    |   privately-owned rights. Reference herein to any specific  commer-   |
  28    |   cial  products,  process,  or  service  by trade name, trademark,   |
  29    |   manufacturer, or otherwise, does not  necessarily  constitute  or   |
  30    |   imply  its endorsement, recommendation, or favoring by the United   |
  31    |   States Government or the University of California. The views  and   |
  32    |   opinions  of authors expressed herein do not necessarily state or   |
  33    |   reflect those of the United States Government or  the  University   |
  34    |   of  California,  and shall not be used for advertising or product   |
  35     \  endorsement purposes.                                              /
  36      ---------------------------------------------------------------------
  37 */
  38
  39 /*
  40                   Floating point exception test module.
  41
  42  */
  43
  44 #include "Python.h"
  45
  46 static PyObject *fpe_error;
  47 PyMODINIT_FUNC initfpetest(void);
  48 static PyObject *test(PyObject *self,PyObject *args);
  49 static double db0(double);
  50 static double overflow(double);
  51 static double nest1(int, double);
  52 static double nest2(int, double);
  53 static double nest3(double);
  54 static void printerr(double);
  55
  56 static PyMethodDef fpetest_methods[] = {
  57     {"test",             (PyCFunction) test,             METH_VARARGS},
  58     {0,0}
  59 };
  60
  61 static PyObject *test(PyObject *self,PyObject *args)
  62 {
  63     double r;
  64
  65     fprintf(stderr,"overflow");
  66     r = overflow(1.e160);
  67     printerr(r);
  68
  69     fprintf(stderr,"\ndiv by 0");
  70     r = db0(0.0);
  71     printerr(r);
  72
  73     fprintf(stderr,"\nnested outer");
  74     r = nest1(0, 0.0);
  75     printerr(r);
  76
  77     fprintf(stderr,"\nnested inner");
  78     r = nest1(1, 1.0);
  79     printerr(r);
  80
  81     fprintf(stderr,"\ntrailing outer");
  82     r = nest1(2, 2.0);
  83     printerr(r);
  84
  85     fprintf(stderr,"\nnested prior");
  86     r = nest2(0, 0.0);
  87     printerr(r);
  88
  89     fprintf(stderr,"\nnested interior");
  90     r = nest2(1, 1.0);
  91     printerr(r);
  92
  93     fprintf(stderr,"\nnested trailing");
  94     r = nest2(2, 2.0);
  95     printerr(r);
  96
  97     Py_INCREF (Py_None);
  98     return Py_None;
  99 }
 100
 101 static void printerr(double r)
 102 {
 103     if(r == 3.1416){
 104       fprintf(stderr,"\tPASS\n");
 105       PyErr_Print();
 106     }else{
 107       fprintf(stderr,"\tFAIL\n");
 108     }
 109     PyErr_Clear();
 110 }
 111
 112 static double nest1(int i, double x)
 113 {
 114   double a = 1.0;
 115
 116   PyFPE_START_PROTECT("Division by zero, outer zone", return 3.1416)
 117   if(i == 0){
 118     a = 1./x;
 119   }else if(i == 1){
 120     /* This (following) message is never seen. */
 121     PyFPE_START_PROTECT("Division by zero, inner zone", return 3.1416)
 122     a = 1./(1. - x);
 123     PyFPE_END_PROTECT(a)
 124   }else if(i == 2){
 125     a = 1./(2. - x);
 126   }
 127   PyFPE_END_PROTECT(a)
 128
 129   return a;
 130 }
 131
 132 static double nest2(int i, double x)
 133 {
 134   double a = 1.0;
 135   PyFPE_START_PROTECT("Division by zero, prior error", return 3.1416)
 136   if(i == 0){
 137     a = 1./x;
 138   }else if(i == 1){
 139     a = nest3(x);
 140   }else if(i == 2){
 141     a = 1./(2. - x);
 142   }
 143   PyFPE_END_PROTECT(a)
 144   return a;
 145 }
 146
 147 static double nest3(double x)
 148 {
 149   double result;
 150   /* This (following) message is never seen. */
 151   PyFPE_START_PROTECT("Division by zero, nest3 error", return 3.1416)
 152   result = 1./(1. - x);
 153   PyFPE_END_PROTECT(result)
 154   return result;
 155 }
 156
 157 static double db0(double x)
 158 {
 159   double a;
 160   PyFPE_START_PROTECT("Division by zero", return 3.1416)
 161   a = 1./x;
 162   PyFPE_END_PROTECT(a)
 163   return a;
 164 }
 165
 166 static double overflow(double b)
 167 {
 168   double a;
 169   PyFPE_START_PROTECT("Overflow", return 3.1416)
 170   a = b*b;
 171   PyFPE_END_PROTECT(a)
 172   return a;
 173 }
 174
 175 PyMODINIT_FUNC initfpetest(void)
 176 {
 177     PyObject *m, *d;
 178
 179     m = Py_InitModule("fpetest", fpetest_methods);
 180     if (m == NULL)
 181         return;
 182     d = PyModule_GetDict(m);
 183     fpe_error = PyErr_NewException("fpetest.error", NULL, NULL);
 184     if (fpe_error != NULL)
 185             PyDict_SetItemString(d, "error", fpe_error);
 186 }