CreateMeasurement.cs

using Waher.Script.Abstraction.Elements;
using Waher.Script.Exceptions;
using Waher.Script.Model;
using Waher.Script.Objects;
using Waher.Script.Units;
 
namespace Waher.Script.Operators
{
    public class CreateMeasurement : BinaryScalarOperator
    {
        public CreateMeasurement(ScriptNode Operand1, ScriptNode Operand2, int Start, int Length, Expression Expression)
            : base(Operand1, Operand2, Start, Length, Expression)
        {
        }
 
        public override IElement EvaluateScalar(IElement Operand1, IElement Operand2, Variables Variables)
        {
            double Magnitude;
            Unit Unit;
            double Error;
 
            if (Operand1.AssociatedObjectValue is IPhysicalQuantity PQ1)
            {
                PhysicalQuantity Q1 = PQ1.ToPhysicalQuantity();
                Magnitude = Q1.Magnitude;
                Unit = Q1.Unit;
            }
            else if (Operand1.AssociatedObjectValue is double D1)
            {
                Magnitude = D1;
                Unit = Unit.Empty;
            }
            else
                throw new ScriptRuntimeException("Expected Physical Quantity our numeric value.", this.LeftOperand);
 
            if (Operand2.AssociatedObjectValue is IPhysicalQuantity PQ2)
            {
                PhysicalQuantity Q2 = PQ2.ToPhysicalQuantity();
                if (Unit == Unit.Empty)
                {
                    Error = Q2.Magnitude;
                    Unit = Q2.Unit;
                }
                else if (!Unit.TryConvert(Q2.Magnitude, Q2.Unit, Unit, out Error))
                    throw new ScriptRuntimeException("Incompatible error unit.", this);
            }
            else if (Operand2.AssociatedObjectValue is double D2)
                Error = D2;
            else
                throw new ScriptRuntimeException("Expected Physical Quantity our numeric value.", this.RightOperand);
 
            return new Measurement(Magnitude, Unit, Error);
        }
    }
}