Mathie is a mathematical expression framework. It creates expression graphs (http://gerritdrost.com/2013/09/mathematical-expression-graphs) and provides an easy way to interface with them. With Mathie you can set up a framework of expressions sharing variables and quickly re-evaluate your expressions when the variables change.
Using annotations and some injection code, Mathie makes it possible to use expressions in a class without writing lots of boilerplate code.
Mathie's focus is quick (re-)evaluation, not fast parsing(although that's still pretty quick as well).
Missing a function/operator? Create an issue if you think it should be included by default or easily extend Mathie if it's a project specific operator!
<dependency>
<groupId>com.gerritdrost.libs.mathie</groupId>
<artifactId>mathie</artifactId>
<version>0.0.1</version>
</dependency>More solid documentation is to follow soon. For now, here are some examples:
public class MathieTest implements Injectable {
@Env
private ExpressionEnvironment env;
@Expr("16/x")
private Expression exp1;
@Var(name = "x", val = 2.0)
private Variable x;
public MathieTest() {
// you could even integrate this little chunk of code into a superclass, but then you can't extend any other
// classes.
Injector.inject(this);
}
@Override
public void injectionDone() {
// x = 2 since we set it to be that, so 16/2 = 8.
System.out.println(exp1);
x.set(8.0);
// 16.0/8.0 obviously is 2.0
System.out.println(exp1);
}
}public class MathieTest {
public MathieTest() {
ExpressionEnvironment t = new ExpressionEnvironment();
Expression e = t.getExpression("2*x");
// when variables are initialized, they are set to 1.0
System.out.println(e);
// let's get that variable object
Variable x = t.getVariable("x");
x.set(5.0);
// Re-evaluation is done automagically
System.out.println(e);
}
}These operators and functions are currently supported. More are being implemented.
- '+' - Addition
- '-' - Subtraction
- '*' - Multiplication
- '/' - Division
- '^' - Exponentiation
- abs(a) - Absolute value
- sin(a) - Sine
- cos(a) - Cosine
- tan(a) - Tangent
- sec(a) - Secant
- csc(a) - Cosecant
- cot(a) - Cotangent
- min(a,b,c,...) - Returns the lowest value of at least 2 parameters
- max(a,b,c,...) - Returns the highest value of at least 2 parameters
- equals(a,b,c,...) - Returns 1.0 if all parameters are equal, returns 0.0 otherwise.
Mathie is provided under the MIT license. More info: