libstdc++-v3/testsuite/20_util/hash/chi2_q_numeric_pattern_set.cc

   1 // Use smaller statistics when running on simulators, so it takes less time.
   2 // For x86_64-linux-gnu SAMPLES=30000 fails, so increase slightly.
   3 // { dg-options "-DSAMPLES=35000" { target simulator } }
   4 // { dg-do run { target c++11 } }
   5
   6 // Copyright (C) 2010-2016 Free Software Foundation, Inc.
   7 //
   8 // This file is part of the GNU ISO C++ Library.  This library is free
   9 // software; you can redistribute it and/or modify it under the
  10 // terms of the GNU General Public License as published by the
  11 // Free Software Foundation; either version 3, or (at your option)
  12 // any later version.
  13 //
  14 // This library is distributed in the hope that it will be useful,
  15 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 // GNU General Public License for more details.
  18 //
  19 // You should have received a copy of the GNU General Public License
  20 // along with this library; see the file COPYING3.  If not see
  21 // <http://www.gnu.org/licenses/>.
  22
  23 #include "chi2_quality.h"
  24
  25 // Tests chi^2 of a set of strings that all have a similar pattern,
  26 // intended to mimic some sort of ID string.
  27 void
  28 test_numeric_pattern_set()
  29 {
  30   bool test __attribute__((unused)) = true;
  31   const unsigned long N = SAMPLES;
  32   const unsigned long k = N/100;
  33   std::vector<std::string> set;
  34   for (unsigned long i = 0; i < N; ++i)
  35     {
  36       long i1 = i % 100000;
  37       long i2 = i / 100000;
  38       char buf[16];
  39       std::sprintf(buf, "XX-%05lu-%05lu", i1, i2);
  40       set.push_back(buf);
  41     }
  42
  43   double chi2 = chi2_hash(set, k);
  44   VERIFY( chi2 < k*1.1 );
  45 }
  46
  47 int
  48 main()
  49 {
  50   test_numeric_pattern_set();
  51   return 0;
  52 }