mcs/class/corlib/System/Double.cs

   1 //
   2 // System.Double.cs
   3 //
   4 // Author:
   5 //   Miguel de Icaza (miguel@ximian.com)
   6 //   Bob Smith       (bob@thestuff.net)
   7 //
   8 // (C) Ximian, Inc.  http://www.ximian.com
   9 // (C) Bob Smith.    http://www.thestuff.net
  10 //
  11
  12 using System.Globalization;
  13 using System.Runtime.CompilerServices;
  14
  15 namespace System {
  16
  17         [Serializable]
  18         public struct Double : IComparable, IFormattable, IConvertible {
  19                 public const double Epsilon = 4.9406564584124650e-324;
  20                 public const double MaxValue =  1.7976931348623157e308;
  21                 public const double MinValue = -1.7976931348623157e308;
  22                 public const double NaN = 0.0d / 0.0d;
  23                 public const double NegativeInfinity = -1.0d / 0.0d;
  24                 public const double PositiveInfinity = 1.0d / 0.0d;
  25
  26                 // VES needs to know about value.  public is workaround
  27                 // so source will compile
  28                 public double value;
  29
  30                 public int CompareTo (object v)
  31                 {
  32                         if (v == null)
  33                                 return 1;
  34
  35                         if (!(v is System.Double))
  36                                 throw new ArgumentException (Locale.GetText ("Value is not a System.Double"));
  37
  38                         if (IsPositiveInfinity(value) && IsPositiveInfinity((double) v)){
  39                                 return 0;
  40                         }
  41
  42                         if (IsNegativeInfinity(value) && IsNegativeInfinity((double) v)){
  43                                 return 0;
  44                         }
  45
  46                         if (IsNaN((double) v)) {
  47                                 if (IsNaN(value))
  48                                         return 0;
  49                                 else
  50                                         return 1;
  51                         }
  52
  53                         return (int) (value - ((double) v));
  54                 }
  55
  56                 public override bool Equals (object o)
  57                 {
  58                         if (!(o is System.Double))
  59                                 return false;
  60
  61                         if (IsNaN ((double)o)) {
  62                                 if (IsNaN(value))
  63                                         return true;
  64                                 else
  65                                         return false;
  66                         }
  67
  68                         return ((double) o) == value;
  69                 }
  70
  71                 public override int GetHashCode ()
  72                 {
  73                         return (int) value;
  74                 }
  75
  76                 public static bool IsInfinity (double d)
  77                 {
  78                         return (d == PositiveInfinity || d == NegativeInfinity);
  79                 }
  80
  81                 public static bool IsNaN (double d)
  82                 {
  83                         return (d != d);
  84                 }
  85
  86                 public static bool IsNegativeInfinity (double d)
  87                 {
  88                         return (d < 0.0d && (d == NegativeInfinity || d == PositiveInfinity));
  89                 }
  90
  91                 public static bool IsPositiveInfinity (double d)
  92                 {
  93                         return (d > 0.0d && (d == NegativeInfinity || d == PositiveInfinity));
  94                 }
  95
  96                 public static double Parse (string s)
  97                 {
  98                         return Parse (s, (NumberStyles.Float | NumberStyles.AllowThousands), null);
  99                 }
 100
 101                 public static double Parse (string s, IFormatProvider fp)
 102                 {
 103                         return Parse (s, (NumberStyles.Float | NumberStyles.AllowThousands), fp);
 104                 }
 105
 106                 public static double Parse (string s, NumberStyles style)
 107                 {
 108                         return Parse (s, style, null);
 109                 }
 110
 111                 public static double Parse (string s, NumberStyles style, IFormatProvider provider)
 112                 {
 113                         if (s == null) throw new ArgumentNullException();
 114                         if (style > NumberStyles.Any)
 115                         {
 116                                 throw new ArgumentException();
 117                         }
 118                         NumberFormatInfo format = NumberFormatInfo.GetInstance(provider);
 119                         if (format == null) throw new Exception("How did this happen?");
 120                         if (s == format.NaNSymbol) return Double.NaN;
 121                         if (s == format.PositiveInfinitySymbol) return Double.PositiveInfinity;
 122                         if (s == format.NegativeInfinitySymbol) return Double.NegativeInfinity;
 123                         string[] sl;
 124                         long integral = 0;
 125                         long fraction = 0;
 126                         long exponent = 1;
 127                         double retval = 0;
 128                         if ((style & NumberStyles.AllowLeadingWhite) != 0)
 129                         {
 130                                 s.TrimStart(null);
 131                         }
 132                         if ((style & NumberStyles.AllowTrailingWhite) != 0)
 133                         {
 134                                 s.TrimEnd(null);
 135                         }
 136                         sl = s.Split(new Char[] {'e', 'E'}, 2);
 137                         if (sl.Length > 1)
 138                         {
 139                                 if ((style & NumberStyles.AllowExponent) == 0)
 140                                 {
 141                                         throw new FormatException();
 142                                 }
 143                                 exponent = long.Parse(sl[1], NumberStyles.AllowLeadingSign, format);
 144                         }
 145                         s = sl[0];
 146                         sl = s.Split(format.NumberDecimalSeparator.ToCharArray(), 2);
 147                         if (sl.Length > 1)
 148                         {
 149                                 if ((style & NumberStyles.AllowDecimalPoint) == 0)
 150                                 {
 151                                         throw new FormatException();
 152                                 }
 153                                 fraction = long.Parse(sl[1], NumberStyles.None, format);
 154                         }
 155                         NumberStyles tempstyle = NumberStyles.None;
 156                         if ((style & NumberStyles.AllowLeadingSign) != 0){
 157                                 tempstyle = NumberStyles.AllowLeadingSign;
 158                         }
 159                         integral = long.Parse(sl[0], tempstyle, format);
 160                         retval = fraction;
 161                         while (retval >1) retval /= 10;
 162                         if (integral < 0){
 163                                 retval -= integral;
 164                                 retval = -retval;
 165                         }
 166                         else retval += integral;
 167                         if (exponent != 1) retval *= Math.Pow(10, exponent);
 168                         return retval;
 169                 }
 170
 171                 public override string ToString ()
 172                 {
 173                         return ToString (null, null);
 174                 }
 175
 176                 public string ToString (IFormatProvider fp)
 177                 {
 178                         return ToString (null, fp);
 179                 }
 180
 181                 public string ToString (string format)
 182                 {
 183                         return ToString (format, null);
 184                 }
 185
 186                 [MonoTODO]
 187                 public string ToString (string format, IFormatProvider fp)
 188                 {
 189                         // FIXME: Need to pass format and provider info to this call too.
 190                         return ToStringImpl(value);
 191                 }
 192
 193                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 194                 private static extern string ToStringImpl (double value);
 195
 196                 // =========== IConvertible Methods =========== //
 197
 198                 public TypeCode GetTypeCode ()
 199                 {
 200                         return TypeCode.Double;
 201                 }
 202
 203                 public object ToType (Type conversionType, IFormatProvider provider)
 204                 {
 205                         return System.Convert.ToType(value, conversionType, provider);
 206                 }
 207
 208                 public bool ToBoolean (IFormatProvider provider)
 209                 {
 210                         return System.Convert.ToBoolean(value);
 211                 }
 212
 213                 public byte ToByte (IFormatProvider provider)
 214                 {
 215                         return System.Convert.ToByte(value);
 216                 }
 217
 218                 public char ToChar (IFormatProvider provider)
 219                 {
 220                         throw new InvalidCastException();
 221                 }
 222
 223                 [CLSCompliant(false)]
 224                 public DateTime ToDateTime (IFormatProvider provider)
 225                 {
 226                         throw new InvalidCastException();
 227                 }
 228
 229                 public decimal ToDecimal (IFormatProvider provider)
 230                 {
 231                         return System.Convert.ToDecimal(value);
 232                 }
 233
 234                 public double ToDouble (IFormatProvider provider)
 235                 {
 236                         return System.Convert.ToDouble(value);
 237                 }
 238
 239                 public short ToInt16 (IFormatProvider provider)
 240                 {
 241                         return System.Convert.ToInt16(value);
 242                 }
 243
 244                 public int ToInt32 (IFormatProvider provider)
 245                 {
 246                         return System.Convert.ToInt32(value);
 247                 }
 248
 249                 public long ToInt64 (IFormatProvider provider)
 250                 {
 251                         return System.Convert.ToInt64(value);
 252                 }
 253
 254                 [CLSCompliant(false)]
 255                 public sbyte ToSByte (IFormatProvider provider)
 256                 {
 257                         return System.Convert.ToSByte(value);
 258                 }
 259
 260                 public float ToSingle (IFormatProvider provider)
 261                 {
 262                         return System.Convert.ToSingle(value);
 263                 }
 264
 265                 string IConvertible.ToString (IFormatProvider provider)
 266                 {
 267                         return ToString(provider);
 268                 }
 269
 270                 [CLSCompliant(false)]
 271                 public ushort ToUInt16 (IFormatProvider provider)
 272                 {
 273                         return System.Convert.ToUInt16(value);
 274                 }
 275
 276                 [CLSCompliant(false)]
 277                 public uint ToUInt32 (IFormatProvider provider)
 278                 {
 279                         return System.Convert.ToUInt32(value);
 280                 }
 281
 282                 [CLSCompliant(false)]
 283                 public ulong ToUInt64 (IFormatProvider provider)
 284                 {
 285                         return System.Convert.ToUInt64(value);
 286                 }
 287         }
 288 }