Math Utilities

using System;
using System.Collections.Generic;
using System.Text;

namespace System.Utilities
{
  internal class MathUtils
  {
    public static int HexToInt(char h)
    {
      if ((h >= '0') && (h <= '9'))
      {
        return (h - '0');
      }
      if ((h >= 'a') && (h <= 'f'))
      {
        return ((h - 'a') + 10);
      }
      if ((h >= 'A') && (h <= 'F'))
      {
        return ((h - 'A') + 10);
      }
      return -1;
    }

    public static char IntToHex(int n)
    {
      if (n <= 9)
      {
        return (char)(n + 48);
      }
      return (char)((n - 10) + 97);
    }

    public static int GetDecimalPlaces(double value)
    {
      // increasing max decimal places above 10 produces weirdness
      int maxDecimalPlaces = 10;
      double threshold = Math.Pow(0.1d, maxDecimalPlaces);

      if (value == 0.0)
        return 0;
      int decimalPlaces = 0;
      while (value - Math.Floor(value) > threshold && decimalPlaces < maxDecimalPlaces)
      {
        value *= 10.0;
        decimalPlaces++;
      }
      return decimalPlaces;
    }

    public static int? Min(int? val1, int? val2)
    {
      if (val1 == null)
        return val2;
      if (val2 == null)
        return val1;

      return Math.Min(val1.Value, val2.Value);
    }

    public static int? Max(int? val1, int? val2)
    {
      if (val1 == null)
        return val2;
      if (val2 == null)
        return val1;

      return Math.Max(val1.Value, val2.Value);
    }

    public static double? Min(double? val1, double? val2)
    {
      if (val1 == null)
        return val2;
      if (val2 == null)
        return val1;

      return Math.Min(val1.Value, val2.Value);
    }

    public static double? Max(double? val1, double? val2)
    {
      if (val1 == null)
        return val2;
      if (val2 == null)
        return val1;

      return Math.Max(val1.Value, val2.Value);
    }
  }
}