/// <summary>
/// Evaluates a math expression of 2 units.
/// </summary>
/// <param name="node">The AST node the evaluation is a part of.</param>
/// <param name="left">The unit on the left</param>
/// <param name="right">The unit on the right</param>
/// <param name="op">The math operator</param>
/// <param name="units"></param>
/// <returns></returns>
public static LObject CalcUnits(AstNode node, LUnit left, LUnit right, Operator op, Units units)
{
double baseUnitsValue = 0;
if (op == Operator.Multiply)
{
baseUnitsValue = left.BaseValue * right.BaseValue;
}
else if (op == Operator.Divide)
{
baseUnitsValue = left.BaseValue / right.BaseValue;
}
else if (op == Operator.Add)
{
baseUnitsValue = left.BaseValue + right.BaseValue;
}
else if (op == Operator.Subtract)
{
baseUnitsValue = left.BaseValue - right.BaseValue;
}
else if (op == Operator.Modulus)
{
baseUnitsValue = left.BaseValue % right.BaseValue;
}
var relativeValue = units.ConvertToRelativeValue(baseUnitsValue, left.SubGroup, null);
var result = new LUnit(relativeValue);
result.BaseValue = baseUnitsValue;
result.Group = left.Group;
result.SubGroup = left.SubGroup;
//result.Value = relativeValue;
var lclass = LangTypeHelper.ConvertToLangUnit(result);
return lclass;
}
/// <summary>
/// Converts the inputs into a LUnit object e.g. 3, "yards"
/// </summary>
/// <param name="value"></param>
/// <param name="unitsName"></param>
/// <returns></returns>
public LUnit ConvertToUnits(double value, string unitsName)
{
// Get length for "feet".
var group = _subGroupsToGroupMap[unitsName];
var sourceUnits = GetUnitsFor(group, unitsName);
// e.g. Convert( 5, "feet")
// Convert 5 feet to inches.
// 1. Convert from source to base
// e.g. 5 feet to 60 inches.
double sourceBaseUnits = value * sourceUnits.ConversionValue;
var unit = new LUnit(value);
unit.Group = group;
unit.SubGroup = unitsName;
unit.BaseValue = sourceBaseUnits;
return(unit);
}
private static void ValidateUnits(LUnit u1, LUnit u2)
{
// Validate.
if (u1 == null || u2 == null)
throw new ArgumentException("Can not add units when 1 unit is empty");
// Check for matching groups e.g. length + length or weight + weight.
if (u1.Group != u2.Group)
throw new ArgumentException("Can not add units " + u1.Group + " to " + u2.Group);
}
/// <summary>
/// Add 2 unites together.
/// </summary>
/// <param name="u1"></param>
/// <param name="u2"></param>
/// <returns></returns>
public static LUnit AddUnits(LUnit u1, LUnit u2)
{
// Validate
LangTypeHelper.ValidateUnits(u1, u2);
// Now convert the values to their base value.
double totalBase = u1.BaseValue + u2.BaseValue;
var unit = new LUnit(totalBase);
unit.BaseValue = totalBase;
unit.Group = u1.Group;
unit.SubGroup = u1.SubGroup;
// Set the value to the converted relative value
// e.g. if u1.subgroup = feet and u2.subgroup == inches.
// then multiply result.basevalue by the conversion value.
// Now convert the units
return unit;
}
/// <summary>
/// Converts the inputs into a LUnit object e.g. 3, "yards"
/// </summary>
/// <param name="value"></param>
/// <param name="unitsName"></param>
/// <returns></returns>
public LUnit ConvertToUnits(double value, string unitsName)
{
// Get length for "feet".
var group = _subGroupsToGroupMap[unitsName];
var sourceUnits = GetUnitsFor(group, unitsName);
// e.g. Convert( 5, "feet")
// Convert 5 feet to inches.
// 1. Convert from source to base
// e.g. 5 feet to 60 inches.
double sourceBaseUnits = value * sourceUnits.ConversionValue;
var unit = new LUnit(value);
unit.Group = group;
unit.SubGroup = unitsName;
unit.BaseValue = sourceBaseUnits;
return unit;
}
/// <summary>
/// Evaluates a math expression of 2 time spans.
/// </summary>
/// <param name="node">The AST node the evaluation is a part of.</param>
/// <param name="lhs">The time on the left hand side</param>
/// <param name="rhs">The time on the right hand side</param>
/// <param name="op">The math operator.</param>
/// <returns></returns>
public static LBool CompareUnits(AstNode node, LUnit lhs, LUnit rhs, Operator op)
{
var result = false;
if (op == Operator.LessThan) result = lhs.BaseValue < rhs.BaseValue;
else if (op == Operator.LessThanEqual) result = lhs.BaseValue <= rhs.BaseValue;
else if (op == Operator.MoreThan) result = lhs.BaseValue > rhs.BaseValue;
else if (op == Operator.MoreThanEqual) result = lhs.BaseValue >= rhs.BaseValue;
else if (op == Operator.EqualEqual) result = lhs.BaseValue == rhs.BaseValue;
else if (op == Operator.NotEqual) result = lhs.BaseValue != rhs.BaseValue;
return new LBool(result);
}