v.4.4.0 (2020-01-14): Gemoni - API improvement

Canonical rounding: Bye bye floating point arithmetic artifacts

ULP rounding is switched of as a default setting (can be enabled / disabled). As a default canonical rounding is switched on (can be disabled / enabled). New methods:

• mXparser.enableCanonicalRounding()
• mXparser.disableCanonicalRounding()
• mXparser.setCanonicalRounding(boolean)
• mXparser.checkIfCanonicalRounding

Example 1

Expression e = new Expression("0.1 + 0.1 + 0.1");
System.out.println("Pure Java             : 0.1 + 0.1 + 0.1 = " + (0.1 + 0.1 + 0.1));
System.out.println("mXparser              : 0.1 + 0.1 + 0.1 = " + e.calculate());
mXparser.disableCanonicalRounding();
System.out.println("mXparser canonical off: 0.1 + 0.1 + 0.1 = " + e.calculate());
===========
Pure Java             : 0.1 + 0.1 + 0.1 = 0.30000000000000004
mXparser              : 0.1 + 0.1 + 0.1 = 0.3
mXparser canonical off: 0.1 + 0.1 + 0.1 = 0.30000000000000004

Example 2

Expression e = new Expression("(-1/6.2)^(-3)");
System.out.println("Pure Java             : (-1/6.2)^(-3) = " + Math.pow(-1/6.2, -3));
System.out.println("mXparser              : (-1/6.2)^(-3) = " + e.calculate());
mXparser.disableCanonicalRounding();
System.out.println("mXparser canonical off: (-1/6.2)^(-3) = " + e.calculate());
===========
Pure Java             : (-1/6.2)^(-3) = -238.32800000000003
mXparser              : (-1/6.2)^(-3) = -238.328
mXparser canonical off: (-1/6.2)^(-3) = -238.32800000000003

Argument extension - analogy to Function Extension

Now you can define user arguments implementing your own algorithm in source code.

Example

class PiMultArgExt implements ArgumentExtension {
    private int multiple = 0;
    public double getArgumentValue() {
        multiple++;
        return  MathConstants.PI * multiple;
    }
    public PiMultArgExt clone() {
        return new PiMultArgExt();
    }
}

Argument x = new Argument("x", new PiMultArgExt());
Expression e = new Expression("x/pi", x);
System.out.println("1st calc exec: " + e.calculate());
System.out.println("2nd calc exec: " + e.calculate());
System.out.println("3rd calc exec: " + e.calculate());
===========
1st calc exec: 1.0
2nd calc exec: 2.0
3rd calc exec: 3.0

Bugs fixed

• [#168], [#18] Exact special trigonometric values
• [#192], [#178] Logical operators precedence
• [#172] "x + 4 * - 2"