Use the MXPARSER framework to perform mathematical calculations in the Java library
Use the MXPARSER framework to perform mathematical calculations in the Java library
Introduction:
MXPARSER is a lightweight mathematical expression analysis engine that can be embedded in the Java application and class library for easy complicated mathematical calculations.It provides rich mathematical functions and operators, supporting variable definition, expression value, equivalent solution and other functions, which is very useful for the application scenarios that require dynamic computing mathematical expression.
Install the MXPARSER framework:
First of all, we need to import the JAR file in the Java project.Download the latest version of the JAR file of MXPARSER and add it to the dependence of the Java project.
Define mathematical expression:
Using the MXPARSER framework, we can define a string containing mathematical expression.For example, we can define a simple arithmetic expression "2+3*5", which contains the addition and multiplication operations.
String expression = "2+3*5";
Create a mxparser parser:
Next, we need to create an example of MXPARSER and pass the defined mathematical expression to it.
Expression e = new Expression(expression);
Analysis of mathematical expression:
Using the Evaluate () method provided by the MXPARSER framework, we can analyze and calculate the defined mathematical expression.
double result = e.calculate();
System.out.println ("Calculation Result:" + Result);
In the above example, we print the resolutions to the console.
Supporting mathematical functions and operators:
In addition to basic addition, subtraction and multiplication, MXPARSER also provides rich mathematical functions, such as SIN, COS, LOG, etc.You can further expand the computing power by using these functions in mathematical expressions.
String expression = "sin(45) + log(100)";
Variable definition and assignment:
The MXPARSER framework also supports definition variables and uses these variables in mathematical expression.The following is an example, how to define a variable and assign a value to it:
Expression e = new Expression("a + b");
e.setVariable("a", 2.5);
e.setVariable("b", 3.8);
double result = e.calculate();
System.out.println ("Calculation Result:" + Result);
In the above examples, "A" and "B" are variable names, which are assigned 2.5 and 3.8 respectively.We can then calculate the value of the expression using the Calculating () method.
Equal solution:
In addition to basic mathematical calculations, MXPARSER also supports solution and unlike formats.For example, we can solve a simple equivalence by using the solve () method:
Expression e = new Expression("x^2 + 2x - 8 = 0");
double[] solutions = e.solve();
System.out.println("解：" + solutions[0]);
System.out.println("解：" + solutions[1]);
In the above example, we solved a secondary equation and printed its two solutions.
Summarize:
Using the MXPARSER framework, we can easily calculate mathematics in the Java applications and libraries.It provides rich mathematical functions and operators, supports variable definition and assignment, and can also solve equal formulas and unequal.I hope this article will help you and use the MXPARSER framework to provide some help.
