/// <summary>
/// Convert decimal to fraction
/// </summary>
/// <param name="value">decimal value to convert</param>
/// <param name="result">result fraction if conversation is succsess</param>
/// <param name="decimalPlaces">precision of considereation frac part of value</param>
/// <param name="trimZeroes">trim zeroes on the right part of the value or not</param>
/// <param name="minPeriodRepeat">minimum period repeating</param>
/// <param name="digitsForReal">precision for determination value to real if period has not been founded</param>
/// <returns></returns>
public static bool FromDecimal(decimal value, out Rational <T> result,
int decimalPlaces = 28, bool trimZeroes = false, decimal minPeriodRepeat = 2, int digitsForReal = 9)
{
var valueStr = value.ToString("0.0000000000000000000000000000", CultureInfo.InvariantCulture);
var strs = valueStr.Split('.');
long intPart = long.Parse(strs[0]);
string fracPartTrimEnd = strs[1].TrimEnd(new char[] { '0' });
string fracPart;
if (trimZeroes)
{
fracPart = fracPartTrimEnd;
decimalPlaces = Math.Min(decimalPlaces, fracPart.Length);
}
else
{
fracPart = strs[1];
}
result = new Rational <T>();
try
{
string periodPart;
bool periodFound = false;
int i;
for (i = 0; i < fracPart.Length; i++)
{
if (fracPart[i] == '0' && i != 0)
{
continue;
}
for (int j = i + 1; j < fracPart.Length; j++)
{
periodPart = fracPart.Substring(i, j - i);
periodFound = true;
decimal periodRepeat = 1;
decimal periodStep = 1.0m / periodPart.Length;
var upperBound = Math.Min(fracPart.Length, decimalPlaces);
int k;
for (k = i + periodPart.Length; k < upperBound; k += 1)
{
if (periodPart[(k - i) % periodPart.Length] != fracPart[k])
{
periodFound = false;
break;
}
periodRepeat += periodStep;
}
if (!periodFound && upperBound - k <= periodPart.Length && periodPart[(upperBound - i) % periodPart.Length] > '5')
{
var ind = (k - i) % periodPart.Length;
var regroupedPeriod = (periodPart.Substring(ind) + periodPart.Remove(ind)).Substring(0, upperBound - k);
ulong periodTailPlusOne = ulong.Parse(regroupedPeriod) + 1;
ulong fracTail = ulong.Parse(fracPart.Substring(k, regroupedPeriod.Length));
if (periodTailPlusOne == fracTail)
{
periodFound = true;
}
}
if (periodFound && periodRepeat >= minPeriodRepeat)
{
result = FromDecimal(strs[0], fracPart.Substring(0, i), periodPart);
break;
}
else
{
periodFound = false;
}
}
if (periodFound)
{
break;
}
}
if (!periodFound)
{
result = new Rational <T>(long.Parse(strs[0]), 1, false);
if (fracPartTrimEnd.Length != 0)
{
result += new Rational <T>(ulong.Parse(fracPartTrimEnd), TenInPower(fracPartTrimEnd.Length));
}
return(fracPartTrimEnd.Length < digitsForReal);
}
return(true);
}
catch
{
return(false);
}
}
public ValueNode SimplifyValues(KnownFuncType?funcType, IList <ValueNode> args)
{
Rational <long> result;
double temp = 0.0;
switch (funcType)
{
case KnownFuncType.Add:
result = args[0].Value;
for (int i = 1; i < args.Count; i++)
{
result += args[i].Value;
}
return(new ValueNode(result));
case KnownFuncType.Sub:
result = args[0].Value;
for (int i = 1; i < args.Count; i++)
{
result -= args[i].Value;
}
return(new ValueNode(result));
case KnownFuncType.Mult:
result = args[0].Value;
for (int i = 1; i < args.Count; i++)
{
result *= args[i].Value;
}
return(new ValueNode(result));
case KnownFuncType.Div:
result = args[0].Value;
for (int i = 1; i < args.Count; i++)
{
result /= args[i].Value;
}
return(new ValueNode(result));
case KnownFuncType.Pow:
if (args[1].Value.ToDouble() == 0.5)
{
temp = Math.Sqrt(args[0].Value.ToDouble());
}
else
{
temp = Math.Pow(args[0].Value.ToDouble(), args[1].Value.ToDouble());
}
break;
case KnownFuncType.Neg:
return(new ValueNode(-args[0].Value));
case KnownFuncType.Sgn:
return(new ValueNode(new Rational <long>((long)Math.Sign(args[0].DoubleValue), 1, false)));
case KnownFuncType.Trunc:
return(new ValueNode(new Rational <long>((long)Math.Truncate(args[0].DoubleValue), 1, false)));
case KnownFuncType.Round:
return(new ValueNode(new Rational <long>((long)Math.Round(args[0].DoubleValue), 1, false)));
case KnownFuncType.Diff:
return(new ValueNode(0));
case KnownFuncType.Sqrt:
temp = Math.Sqrt(args[0].DoubleValue);
break;
case KnownFuncType.Sin:
temp = Math.Sin(args[0].DoubleValue);
break;
case KnownFuncType.Cos:
temp = Math.Cos(args[0].DoubleValue);
break;
case KnownFuncType.Tan:
temp = Math.Tan(args[0].DoubleValue);
break;
case KnownFuncType.Cot:
temp = 1 / Math.Tan(args[0].DoubleValue);
break;
case KnownFuncType.Arcsin:
temp = Math.Asin(args[0].DoubleValue);
break;
case KnownFuncType.Arccos:
temp = Math.Acos(args[0].DoubleValue);
break;
case KnownFuncType.Arctan:
temp = Math.Atan(args[0].DoubleValue);
break;
case KnownFuncType.Arccot:
temp = Math.PI / 2 - Math.Atan(args[0].DoubleValue);
break;
case KnownFuncType.Sinh:
temp = Math.Sinh(args[0].DoubleValue);
break;
case KnownFuncType.Cosh:
temp = Math.Cosh(args[0].DoubleValue);
break;
case KnownFuncType.Arcsinh:
temp = Math.Log(args[0].DoubleValue + Math.Sqrt(args[0].DoubleValue * args[0].DoubleValue + 1));
break;
case KnownFuncType.Arcosh:
temp = Math.Log(args[0].DoubleValue + Math.Sqrt(args[0].DoubleValue * args[0].DoubleValue - 1));
break;
case KnownFuncType.Exp:
temp = Math.Exp(args[0].DoubleValue);
break;
case KnownFuncType.Ln:
temp = Math.Log(args[0].DoubleValue);
break;
case KnownFuncType.Log10:
temp = Math.Log10(args[0].DoubleValue);
break;
case KnownFuncType.Log:
temp = Math.Log(args[0].DoubleValue, args[1].DoubleValue);
break;
case KnownFuncType.Abs:
temp = Math.Abs(args[0].DoubleValue);
break;
default:
return(null);
}
try
{
if (Rational <long> .FromDecimal((decimal)temp, out result, 14, false, 4, 8))
{
return(new ValueNode(result));
}
}
catch
{
}
return(null);
}
public CalculatedNode(Rational <long> value)
{
_value = (double)value.ToDecimal(CultureInfo.InvariantCulture);
Name = _value.ToString(CultureInfo.InvariantCulture);
}
private MathFuncNode MultValues(MathFuncNode funcNode)
{
var values = funcNode.Children
.Where(child => child is ValueNode)
.Cast <ValueNode>()
.Select(valueChild => valueChild.Value);
values = values.Concat(funcNode.Children
.Where(child => child is FuncNode childFuncNode && childFuncNode.FunctionType == KnownFuncType.Neg)
.Select(valueChild => new Rational <long>(-1, 1)));
Rational <long> result = 1;
foreach (var value in values)
{
result *= value;
}
if (result == 0)
{
return(new ValueNode(0));
}
var notValuesNodes = funcNode.Children
.Where(child => !(child is ValueNode) && !(child is FuncNode childFuncNode && childFuncNode.FunctionType == KnownFuncType.Neg))
.Concat(funcNode.Children
.Where(child => child is FuncNode childFuncNode && childFuncNode.FunctionType == KnownFuncType.Neg)
.Select(negChild => negChild.Children[0])).ToList();
if (result == 1)
{
return(notValuesNodes.Count == 0 ? new ValueNode(1) :
notValuesNodes.Count == 1 ? notValuesNodes.First() :
new FuncNode(KnownFuncType.Mult, notValuesNodes));
}
else if (result == -1)
{
return(notValuesNodes.Count == 0 ? (MathFuncNode)(new ValueNode(-1)) :
notValuesNodes.Count == 1 ? new FuncNode(KnownFuncType.Neg, notValuesNodes.First()) :
new FuncNode(KnownFuncType.Neg, new FuncNode(KnownFuncType.Mult, notValuesNodes)));
}
else
{
if (notValuesNodes.Count == 0)
{
return(new ValueNode(result));
}
else
{
if (result < 0)
{
notValuesNodes.Add(new ValueNode(-result));
return(new FuncNode(KnownFuncType.Neg, new FuncNode(KnownFuncType.Mult, notValuesNodes)));
}
else
{
notValuesNodes.Add(new ValueNode(result));
return(new FuncNode(KnownFuncType.Mult, notValuesNodes));
}
}
}
}
