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1 // Copyright (c) 1997-2009 Nokia Corporation and/or its subsidiary(-ies). |
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2 // All rights reserved. |
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3 // This component and the accompanying materials are made available |
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4 // under the terms of the License "Symbian Foundation License v1.0" |
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5 // which accompanies this distribution, and is available |
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6 // at the URL "http://www.symbianfoundation.org/legal/sfl-v10.html". |
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7 // |
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8 // Initial Contributors: |
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9 // Nokia Corporation - initial contribution. |
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10 // |
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11 // Contributors: |
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12 // |
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13 // Description: |
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14 // e32\euser\maths\um_spec.cpp |
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15 // Functions to check for and set special values |
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16 // |
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17 // |
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18 // |
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19 |
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20 |
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21 #include "um_std.h" |
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22 |
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23 |
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24 |
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25 |
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26 #ifndef __REALS_MACHINE_CODED__ |
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27 EXPORT_C TBool Math::IsZero(const TReal &aVal) |
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28 /** |
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29 Determines whether a value is zero. |
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30 |
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31 @param aVal A reference to the value to be checked. |
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32 |
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33 @return True, if aVal is zero; false, otherwise. |
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34 */ |
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35 { |
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36 |
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37 SReal64 *pS=(SReal64 *)&aVal; |
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38 |
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39 if (pS->msm==0U && pS->lsm==0U && pS->exp==(unsigned)KTReal64ZeroExponent) |
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40 return TRUE; |
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41 else |
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42 return FALSE; |
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43 } |
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44 |
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45 |
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46 |
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47 |
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48 EXPORT_C TBool Math::IsNaN(const TReal &aVal) |
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49 /** |
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50 Determines whether a value is not a number. |
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51 |
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52 @param aVal A reference to the value to be checked. |
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53 |
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54 @return True, if aVal is not a number; false, otherwise. |
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55 */ |
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56 { |
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57 |
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58 SReal64 *pS=(SReal64 *)&aVal; |
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59 |
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60 if (pS->exp==(unsigned)KTReal64SpecialExponent && (pS->msm|pS->lsm)!= 0U) |
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61 return TRUE; |
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62 else |
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63 return FALSE; |
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64 } |
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65 |
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66 |
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67 |
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68 |
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69 EXPORT_C TBool Math::IsInfinite(const TReal &aVal) |
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70 /** |
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71 Determines whether a value is infinite. |
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72 |
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73 @param aVal A reference to the value to be checked. |
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74 |
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75 @return True, if aVal is infinite; false, otherwise. |
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76 */ |
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77 { |
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78 |
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79 SReal64 *pS=(SReal64 *)&aVal; |
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80 |
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81 if (pS->msm==0U && pS->lsm==0U && pS->exp==(unsigned)KTReal64SpecialExponent) |
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82 return TRUE; |
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83 else |
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84 return FALSE; |
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85 } |
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86 |
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87 |
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88 |
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89 |
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90 EXPORT_C TBool Math::IsFinite(const TReal &aVal) |
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91 /** |
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92 Determines whether a value is finite. |
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93 |
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94 In this context, a value is finite if it is a valid number and |
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95 is not infinite. |
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96 |
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97 @param aVal A reference to the value to be checked. |
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98 |
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99 @return True, if aVal is finite; false, otherwise. |
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100 */ |
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101 { |
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102 |
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103 SReal64 *pS=(SReal64 *)&aVal; |
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104 |
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105 if (pS->exp!=(unsigned)KTReal64SpecialExponent) |
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106 return TRUE; |
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107 else |
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108 return FALSE; |
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109 } |
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110 |
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111 |
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112 |
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113 |
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114 EXPORT_C void Math::SetZero(TReal &aVal,TInt aSign) |
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115 // |
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116 // Constructs zeros, assuming default sign is positive |
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117 // |
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118 { |
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119 |
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120 SReal64 *pS=(SReal64 *)&aVal; |
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121 pS->sign=aSign; |
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122 pS->exp=KTReal64ZeroExponent; |
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123 pS->msm=0; |
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124 pS->lsm=0; |
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125 } |
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126 |
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127 |
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128 |
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129 |
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130 EXPORT_C void Math::SetNaN(TReal &aVal) |
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131 // |
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132 // Constructs NaN (+ve sign for Java) |
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133 // |
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134 { |
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135 |
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136 SReal64 *pS=(SReal64 *)&aVal; |
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137 pS->sign=0; |
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138 pS->exp=KTReal64SpecialExponent; |
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139 pS->msm=0xfffffu; |
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140 pS->lsm=0xffffffffu; |
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141 } |
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142 |
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143 |
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144 |
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145 |
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146 EXPORT_C void Math::SetInfinite(TReal &aVal,TInt aSign) |
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147 // |
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148 // Constructs infinities |
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149 // |
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150 { |
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151 |
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152 SReal64 *pS=(SReal64 *)&aVal; |
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153 pS->sign=aSign; |
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154 pS->exp=KTReal64SpecialExponent; |
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155 pS->msm=0; |
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156 pS->lsm=0; |
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157 } |
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158 #endif |
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159 |