/// <summary>
/// Mul operator *: Multiply two values.
/// </summary>
/// <param name="left">A value to multiply with</param>
/// <param name="right">A value to multiply</param>
/// <returns>(left.value * right.value, [Normalised(left.scale right.scale)])</returns>
public static DoubleST Mul(DoubleST left, DoubleST right)
{
var result = new DoubleST(left.Value * right.Value, left.Scale);
result.Append(right.Scale);
return(result);
}
/// <summary>
/// BaseFactor: expressing the ScaleType (1, [target]) in basic Units of the ScaleType
/// </summary>
/// <remarks>
/// Example: ScaleType (1, [cm])
/// The BaseUnit for [cm] is Unit.Base, the meter [m]
/// BaseNormal = (0.01, [m]), (1, [cm]) = (0.01, [m])
///
/// This value is usefull for checking if a conversion is possible from one value
/// to another. Both value BaseFactors must have identical scales.
///
/// Pitfall: Do not use for conversion!
/// e.g.:
/// (C1, [m]) = (1, [ft]) = BaseFactor([ft])
/// (C2, [m]) = (1, [cm]) = BaseFactor([cm])
/// then
/// (y, [ft]) = (x, [cm])*(C2, [m])/(C1, [m])
/// = (x*C2/C1, [cm])
/// The value appears to be correct but the scale is incorrect.
///
/// Note: The relation between
/// (c1, [Unit.Base]) = BaseNormal([Unit]) and
/// (C1, [Unit]) = BaseFactor([Unit])
/// is c1 = 1/C1
/// </remarks>
/// <seealso cref="BaseNormal"/>
/// <param name="target">A list of ScaledUnit instances that form the scale to use.</param>
/// <returns>
/// (x, [Unit.Base]), the conversion of (1, [Unit]) where Unit.Base is in { [m], [g], [s],... }
/// </returns>
static DoubleST BaseFactor(Scale target)
{
var result = new DoubleST(1.0);
foreach (var s in target)
{
result.Append(s.Unit.Base(), s.Exp);
result = result / s.Factor();
}
return(result);
}
/// <summary>
/// Div operator /: Divide two values.
/// </summary>
/// <param name="left">A value to divide to</param>
/// <param name="right">A value to divide with</param>
/// <returns>(left.value / right.value, [Normalised(left.scale, right.scale^-1)])</returns>
public static DoubleST Div(DoubleST left, DoubleST right)
{
if (right.Value == 0.0)
{
throw new DivideByZeroException($"{left} / {right} ");
}
var result = new DoubleST(left.Value / right.Value, left.Scale);
result.Append(right.Scale, reciproce: true);
return(result);
}