MathParser.org-mXparser 数学表达式计算
背景
在系统中需要计算公式，参数可以配置，类似excel的情况，可以实现数据的计算。
mXparser
实例
public static void main(String[] args) throws InterruptedException {
Argument days = new Argument("days = 30");
Expression min = new Expression("min(days/10,1)", days);
mXparser.consolePrint(min.getExpressionString() + "----" + min.calculate());
Expression e = new Expression("2-(32-4)/(23+4/5)-(2-4)*(4+6-98.2)+4");
mXparser.consolePrintln("Res: " + e.getExpressionString() + " = " + e.calculate());
Expression abs = new Expression("abs(-1)");
mXparser.consolePrintln("Res: " + abs.getExpressionString() + " = " + abs.calculate());
Expression sqrt = new Expression("sqrt(2)");
mXparser.consolePrintln("Res: " + sqrt.getExpressionString() + " = " + sqrt.calculate());
Function A = new Function("t(a,b) = 1/2 * a *b");
Expression expression = new Expression("t(2,4)",A);
mXparser.consolePrintln(expression.getExpressionString() +"-----------"+expression.calculate());
Argument a = new Argument("a = 3");
Argument b = new Argument("b = 3");
Argument h = new Argument("h = 4");
Expression expression1 = new Expression("t(b,h)",A,b,h,a);
mXparser.consolePrintln(expression1.getExpressionString() +"-----------"+expression1.calculate());
Expression expression2 = new Expression("1/2 * a *b",A,b,h,a);
mXparser.consolePrintln(expression2.getExpressionString() +"-----------"+expression2.calculate());
}
