sal/qa/inc/valueequal.hxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
   3  * This file is part of the LibreOffice project.
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   5  * This Source Code Form is subject to the terms of the Mozilla Public
   6  * License, v. 2.0. If a copy of the MPL was not distributed with this
   7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
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   9  * This file incorporates work covered by the following license notice:
  10  *
  11  *   Licensed to the Apache Software Foundation (ASF) under one or more
  12  *   contributor license agreements. See the NOTICE file distributed
  13  *   with this work for additional information regarding copyright
  14  *   ownership. The ASF licenses this file to you under the Apache
  15  *   License, Version 2.0 (the "License"); you may not use this file
  16  *   except in compliance with the License. You may obtain a copy of
  17  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
  18  */
  19
  20 #include <math.h>
  21
  22 #define PREC_float 1
  23 #define PREC_double 2
  24 #define PREC_long_double 3
  25
  26 template<class T>
  27 bool is_equal(T x, T y, sal_Int16 _nPrec)
  28 {
  29     // due to the fact that this check looks only if both values are equal
  30     // we only need to look on one value
  31
  32     // 14 digits will announce the checkPrecisionSize
  33
  34     sal_Int32 nPRECISION;
  35     switch(_nPrec)
  36     {
  37     case PREC_float:
  38         nPRECISION = 6;
  39         break;
  40     case PREC_double:
  41         nPRECISION = 14;
  42         break;
  43     case PREC_long_double:
  44         nPRECISION = 20;
  45         break;
  46     default:
  47         nPRECISION = 2;
  48     }
  49
  50     if (x < 0)
  51     {
  52         x = -x;
  53     }
  54     if (y < 0)
  55     {
  56         y = -y;
  57     }
  58
  59     if (_nPrec != PREC_long_double)
  60     {
  61         printf("double equal: %.20f\n", x);
  62         printf("              %.20f\n", y);
  63     }
  64     //here nPrecOfN is the number after dot
  65     sal_Int32 nBeforeDot = sal_Int32( log10(x) );
  66     if ( nBeforeDot < 0)
  67     {
  68          nBeforeDot = 0;
  69     }
  70     //printf("nPRECISION is  %d\n", nPRECISION);
  71     sal_Int32 nPrecOfN = -nPRECISION + nBeforeDot;
  72
  73     if (_nPrec != PREC_long_double)
  74         printf("nPrecOfN is  %" SAL_PRIdINT32 "\n", nPrecOfN);
  75
  76     double nPrec = pow(0.1, -nPrecOfN);
  77
  78     if (_nPrec != PREC_long_double)
  79         printf("        prec: %.20f\n", nPrec);
  80
  81     double nDelta = fabs( x - y ) ;
  82
  83     if (_nPrec != PREC_long_double)
  84     {
  85         printf("       delta: %.20f\n", nDelta);
  86         printf("       nPrec: %.20f\n", nPrec);
  87         printf("delta must be less or equal to prec\n\n");
  88     }
  89
  90     if (nDelta > nPrec)
  91     {
  92         // values are not equal
  93         return false;
  94     }
  95
  96     // values are equal
  97     return true;
  98 }
  99
 100 bool is_float_equal(float x, float y)
 101 {
 102     return is_equal<float>(x, y, PREC_float);
 103 }
 104 bool is_double_equal(double x, double y)
 105 {
 106     return is_equal<double>(x, y, PREC_double);
 107 }
 108
 109 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */