Merge

2 files changed, 314 insertions, 0 deletions

diff --git a/Source/Basetypes/Basetypes.csproj b/Source/Basetypes/Basetypes.csproj
index ceccc5cf..a7b7cb71 100644
--- a/Source/Basetypes/Basetypes.csproj
+++ b/Source/Basetypes/Basetypes.csproj
@@ -148,6 +148,7 @@
     <Compile Include="..\version.cs">

       <Link>version.cs</Link>

     </Compile>

+    <Compile Include="BigDec.cs" />

     <Compile Include="BigNum.cs" />

     <Compile Include="Rational.cs" />

     <Compile Include="Set.cs" />

diff --git a/Source/Basetypes/BigDec.cs b/Source/Basetypes/BigDec.cs
new file mode 100644
index 00000000..6059539b
--- /dev/null
+++ b/Source/Basetypes/BigDec.cs
@@ -0,0 +1,313 @@
+//-----------------------------------------------------------------------------

+//

+// Copyright (C) Microsoft Corporation.  All Rights Reserved.

+//

+//-----------------------------------------------------------------------------

+using System;

+using System.Text;

+using System.Diagnostics.Contracts;

+

+

+namespace Microsoft.Basetypes {

+  using BIM = System.Numerics.BigInteger;

+

+

+  /// <summary>

+  /// A representation of decimal values.

+  /// </summary>

+  public struct BigDec {

+

+    // the internal representation

+    [Rep]

+    internal readonly BIM mantissa;

+    [Rep]

+    internal readonly int exponent;

+

+    public BIM Mantissa {

+      get {

+        return mantissa;

+      }

+    }

+

+    public int Exponent {

+      get {

+        return exponent;

+      }

+    }

+

+    public static readonly BigDec ZERO = FromInt(0);

+    private static readonly BIM ten = new BIM(10);

+

+

+    ////////////////////////////////////////////////////////////////////////////

+    // Constructors

+

+    [Pure]

+    public static BigDec FromInt(int v) {

+      return new BigDec(v, 0);

+    }

+

+    [Pure]

+    public static BigDec FromString(string v) {

+      if (v == null) throw new FormatException();

+

+      BIM integral = BIM.Zero;

+      BIM fraction = BIM.Zero;

+      int exponent = 0;

+

+      int len = v.Length;

+

+      int i = v.IndexOf('e');

+      if (i >= 0) {

+        if (i + 1 == v.Length) throw new FormatException();

+        exponent = Int32.Parse(v.Substring(i + 1, len - i - 1));

+        len = i;

+      }

+

+      int fractionLen = 0;

+      i = v.IndexOf('.');

+      if (i >= 0) {

+        if (i + 1 == v.Length) throw new FormatException();

+        fractionLen = len - i - 1;

+        fraction = BIM.Parse(v.Substring(i + 1, fractionLen));

+        len = i;

+      }

+

+      integral = BIM.Parse(v.Substring(0, len));

+

+      if (!fraction.IsZero) {

+        while (fractionLen > 0) {

+          integral = integral * ten;

+          exponent = exponent - 1;

+          fractionLen = fractionLen - 1;

+        }

+      }

+

+      return new BigDec(integral + fraction, exponent);

+    }

+

+    internal BigDec(BIM mantissa, int exponent) {

+      if (mantissa.IsZero) {

+        this.mantissa = mantissa;

+        this.exponent = 0;

+      }

+      else {

+        while (mantissa % ten == BIM.Zero) {

+          mantissa = mantissa / ten;

+          exponent = exponent + 1;

+        }

+        this.mantissa = mantissa;

+        this.exponent = exponent;

+      }

+    }

+

+

+    ////////////////////////////////////////////////////////////////////////////

+    // Basic object operations

+

+    [Pure]

+    [Reads(ReadsAttribute.Reads.Nothing)]

+    public override bool Equals(object obj) {

+      if (obj == null)

+        return false;

+      if (!(obj is BigDec))

+        return false;

+

+      return (this == (BigDec)obj);

+    }

+

+    [Pure]

+    public override int GetHashCode() {

+      return this.mantissa.GetHashCode() * 13 + this.exponent.GetHashCode();

+    }

+

+    [Pure]

+    public override string/*!*/ ToString() {

+      Contract.Ensures(Contract.Result<string>() != null);

+      return String.Format("{0}e{1}", this.mantissa.ToString(), this.exponent.ToString());

+    }

+

+

+    ////////////////////////////////////////////////////////////////////////////

+    // Conversion operations

+

+    [Pure]

+    public BIM Floor(BIM? minimum, BIM? maximum) {

+      BIM n = this.mantissa;

+      

+      if (this.exponent >= 0) {

+        int e = this.exponent;

+        while (e > 0 && (minimum == null || minimum <= n) && (maximum == null || n <= maximum)) {

+          n = n * ten;

+          e = e - 1;

+        }

+      }

+      else {

+        int e = -this.exponent;

+        while (e > 0 && !n.IsZero) {

+          n = n / ten;

+          e = e - 1;

+        }

+      }

+

+      if (minimum != null && n < minimum)

+        return (BIM)minimum;

+      else if (maximum != null && maximum < n)

+        return (BIM)maximum;

+      else

+        return n;

+    }

+

+    [Pure]

+    public String ToDecimalString(int maxDigits) {

+      string s = this.mantissa.ToString();

+      int digits = (this.mantissa >= 0) ? s.Length : s.Length - 1;

+      BIM max = BIM.Pow(10, maxDigits);

+      BIM min = -max;

+

+      if (this.exponent >= 0) {

+        if (maxDigits < digits || maxDigits - digits < this.exponent) {

+          return String.Format("{0}.0", (this.mantissa >= 0) ? max.ToString() : min.ToString());

+        }

+        else {

+          return String.Format("{0}{1}.0", s, new string('0', this.exponent));

+        }

+      }

+      else {

+        int exp = -this.exponent;

+

+        if (exp < digits) {

+          int intDigits = digits - exp;

+          if (maxDigits < intDigits) {

+            return String.Format("{0}.0", (this.mantissa >= 0) ? max.ToString() : min.ToString());

+          }

+          else {

+            int fracDigits = Math.Min(maxDigits, digits - intDigits);

+            return String.Format("{0}.{1}", s.Substring(0, intDigits), s.Substring(intDigits, fracDigits));

+          }

+        }

+        else {

+          int fracDigits = Math.Min(maxDigits, digits);

+          return String.Format("0.{0}{1}", new string('0', exp - fracDigits), s.Substring(0, fracDigits));

+        }

+      }

+    }

+

+

+    ////////////////////////////////////////////////////////////////////////////

+    // Basic arithmetic operations

+

+    [Pure]

+    public BigDec Abs {

+      get {

+        return new BigDec(BIM.Abs(this.mantissa), this.exponent);

+      }

+    }

+

+    [Pure]

+    public BigDec Negate {

+      get {

+        return new BigDec(BIM.Negate(this.mantissa), this.exponent);

+      }

+    }

+

+    [Pure]

+    public static BigDec operator -(BigDec x) {

+      return x.Negate;

+    }

+

+    [Pure]

+    public static BigDec operator +(BigDec x, BigDec y) {

+      BIM m1 = x.mantissa;

+      int e1 = x.exponent;

+      BIM m2 = y.mantissa;

+      int e2 = y.exponent;

+      if (e2 < e1) {

+        m1 = y.mantissa;

+        e1 = y.exponent;

+        m2 = x.mantissa;

+        e2 = x.exponent;

+      }

+

+      while (e2 > e1) {

+        m2 = m2 * ten;

+        e2 = e2 - 1;

+      }

+

+      return new BigDec(m1 + m2, e1);

+    }

+

+    [Pure]

+    public static BigDec operator -(BigDec x, BigDec y) {

+      return x + y.Negate;

+    }

+

+    [Pure]

+    public static BigDec operator *(BigDec x, BigDec y) {

+      return new BigDec(x.mantissa * y.mantissa, x.exponent + y.exponent);

+    }

+

+

+    ////////////////////////////////////////////////////////////////////////////

+    // Some basic comparison operations

+

+    public bool IsPositive {

+      get {

+        return (this.mantissa > BIM.Zero);

+      }

+    }

+

+    public bool IsNegative {

+      get {

+        return (this.mantissa < BIM.Zero);

+      }

+    }

+

+    public bool IsZero {

+      get {

+        return this.mantissa.IsZero;

+      }

+    }

+

+    [Pure]

+    public int CompareTo(BigDec that) {

+      if (this.mantissa == that.mantissa && this.exponent == that.exponent) {

+        return 0;

+      }

+      else {

+        BigDec d = this - that;

+        return d.IsNegative ? -1 : 1;

+      }

+    }

+

+    [Pure]

+    public static bool operator ==(BigDec x, BigDec y) {

+      return x.CompareTo(y) == 0;

+    }

+

+    [Pure]

+    public static bool operator !=(BigDec x, BigDec y) {

+      return x.CompareTo(y) != 0;

+    }

+

+    [Pure]

+    public static bool operator <(BigDec x, BigDec y) {

+      return x.CompareTo(y) < 0;

+    }

+

+    [Pure]

+    public static bool operator >(BigDec x, BigDec y) {

+      return x.CompareTo(y) > 0;

+    }

+

+    [Pure]

+    public static bool operator <=(BigDec x, BigDec y) {

+      return x.CompareTo(y) <= 0;

+    }

+

+    [Pure]

+    public static bool operator >=(BigDec x, BigDec y) {

+      return x.CompareTo(y) >= 0;

+    }

+  }

+}