MathExpressionCompiler

Parse math strings into Delegates for real and complex numbers.

Getting started

There are only two methods and two number spaces to choose from, but more to this later. Let's run the most basic form.

var del = MathExpressionCompiler.CreateDelegate<double>("length + 3 * height", out string[] variableNameList);
Console.WriteLine($"[{string.Join(", ", variableNameList)}]");
//> [length, height]
Console.WriteLine(del.DynamicInvoke(4,7));
//>  25

If you want to change number space to complex

var del = MathExpressionCompiler.CreateDelegate<Complex>("length + 3 * height", out string[] variableNameList);
Console.WriteLine($"[{string.Join(", ", variableNameList)}]");
//> [length, height]
Console.WriteLine(del.DynamicInvoke(new Complex(4,2),new Complex(5,7)));
//>  <19; 23>

Forcing input to double

When using the complex numberspace, you can also create a delegate that takes doubles and just sets the imaginry part to 0.

var del = MathExpressionCompiler.CreateDelegateWithDoubleParameters<Complex>("length + 3 * height", out string[] variableNameList);
Console.WriteLine(del.DynamicInvoke(4,7));
//> <25; 0>

Since i will be parsed as the complex unit you can still implement complex functions this way.

var del = MathExpressionCompiler.CreateDelegateWithDoubleParameters<Complex>("a + b * i", out string[] variableNameList);
Console.WriteLine(del.DynamicInvoke(4,7));
//> <4; 7>

Another usecase for this is entering a value using polar coordinates

var del = MathExpressionCompiler.CreateDelegateWithDoubleParameters<Complex>("polar(a,b)", out string[] variableNameList);
Console.WriteLine(del.DynamicInvoke(4,7));
//> <3,0156090173732184; 2,6279463948751562>

General Rules

1. All strings get transformed to lowercase.
2. Use * to connect numbers and variables. For now sloppy notation will not get fixed.
3. To prevent scoping confusion all methods like sqrt, sin, cos... need to be followed by (<term>).
4. Methods taking multiple parameters like sum have their parameters seperated by , : sum(x,1,4,x/2).
5. Spaces can be used to make you equations easier to read.

Implemented functions

In the folowing table all parameters can be any term except the ones being shown as VAR. They have to be a variable name.

Operation	Syntax	Description
Addition	x + y	Add x and y
Subtraction	x - y	Subtract y from x
Multiplication	x * y	Multiply x and y
Division	x / y	Divide x by y
Power	x ^ y	x to the power of y
Sinus	sin(x)	Sinus of x
Cosinus	cos(x)	Cosinus of x
Tangent	tan(x)	Tangent of x
Square Root	sqrt(x)	Square root of x
Polar	polar(x,y)	Create Complex from polar using x.Real and y.Real
Sum	sum(VAR,a,b,c)	Add together each iteration of c. Start Var = a and end VAR = b