private async void HandleIntegralSolvingClick(object sender, RoutedEventArgs e)
{
if (_ctx.IntegralStrategy == null)
{
return;
}
Spinner.Visibility = Visibility.Visible;
var vars = FormulaVariablesStack.Children.OfType <TextBox>().Select(t => t.Text).ToList();
var func = new Math.Expression(_ctx.Formula.Representation);
for (var i = 0; i < vars.Count; i++)
{
func.addConstants(new Math.Constant($"{_ctx.Formula.VariableNames[i]} = {Convert.ToDouble(vars[i]).ToString(CultureInfo.InvariantCulture)}"));
}
var from = Convert.ToInt32(_ctx.From);
var to = Convert.ToInt32(_ctx.To);
if (to <= from)
{
MessageBox.Show("From number must be lower then to number!");
}
else
{
await CalculateIntegral(from, to, func);
}
Spinner.Visibility = Visibility.Hidden;
}
public static void Start()
{
/*
* Tutorial for the mXparser version 1.0
* Mariusz Gromada 2010-01-10
*/
/*
* Simple & complex arithmetic expressions, large math functions collection
* User defined arguments, functions, constants
* Calculus operations (i.e. differentiation, integration)
* Summation and product operations
* User defined recursive functions
* Boolean operators
* and many more...
*
*/
/*
* Start from the license
*/
Expression e = new Expression();
mXparser.consolePrintln(e.getLicense());
mXparser.consolePrintln();
/*
* Using help
*/
mXparser.consolePrintln();
mXparser.consolePrintln(e.getHelp());
/*
* Full line searching
*/
mXparser.consolePrintln();
mXparser.consolePrintln(e.getHelp("sine"));
mXparser.consolePrintln();
mXparser.consolePrintln(e.getHelp("inver"));
/*
* Simple expression
*/
Expression e1 = new Expression("2+1");
mXparser.consolePrintln(e1.getExpressionString() + " = " + e1.calculate());
e1.setExpressionString("2-1");
mXparser.consolePrintln(e1.getExpressionString() + " = " + e1.calculate());
/* operators */
Expression e2 = new Expression("2-(32-4)/(23+(4)/(5))-(2-4)*(4+6-98.2)+4");
mXparser.consolePrintln(e2.getExpressionString() + " = " + e2.calculate());
/* power function */
Expression e3 = new Expression("2^3+2^(-3)+2^3^(-4)");
mXparser.consolePrintln(e3.getExpressionString() + " = " + e3.calculate());
/*
* Relations
*/
Expression e4 = new Expression("2=3");
mXparser.consolePrintln(e4.getExpressionString() + " = " + e4.calculate());
Expression e5 = new Expression("2<3");
mXparser.consolePrintln(e5.getExpressionString() + " = " + e5.calculate());
Expression e6 = new Expression("(2=3) | (2<3)");
mXparser.consolePrintln(e6.getExpressionString() + " = " + e6.calculate());
Expression e7 = new Expression("(2=3) & (2<3)");
mXparser.consolePrintln(e7.getExpressionString() + " = " + e7.calculate());
/* 1 arg functions */
Expression e8 = new Expression("sin(2)-cos(3)");
mXparser.consolePrintln(e8.getExpressionString() + " = " + e8.calculate());
/* 2 args functions */
Expression e9 = new Expression("min(3,4) + max(-2,-1)");
mXparser.consolePrintln(e9.getExpressionString() + " = " + e9.calculate());
/* binomial coefficient */
Expression e10 = new Expression("C(10,5)");
mXparser.consolePrintln(e10.getExpressionString() + " = " + e10.calculate());
/* 3 args functions */
/* conditions */
Expression e11 = new Expression("if(2<3,1,0)");
mXparser.consolePrintln(e11.getExpressionString() + " = " + e11.calculate());
Expression e12 = new Expression("if(3<2,1,0)");
mXparser.consolePrintln(e12.getExpressionString() + " = " + e12.calculate());
Expression e13 = new Expression("if(3<2, 1, if(1=1, 5, 0) )");
mXparser.consolePrintln(e13.getExpressionString() + " = " + e13.calculate());
/*
* Free Arguments
*/
Argument x = new Argument("x", 1);
Argument y = new Argument("y", 2);
Argument z = new Argument("z", 3);
Argument n = new Argument("n", 4);
Expression e14 = new Expression("sin(x+y)-cos(y/z)", x, y, z);
mXparser.consolePrintln(e14.getExpressionString() + " = " + e14.calculate());
Expression e15 = new Expression("if(x>y, x-z, if(y<z, sin(x+y), cos(z)) )", x, y, z);
mXparser.consolePrintln(e15.getExpressionString() + " = " + e15.calculate());
x.setArgumentValue(5);
mXparser.consolePrintln(x.getArgumentName() + " = " + x.getArgumentValue());
/*
* Dependent arguments
*/
y = new Argument("y","2*x+5", x);
mXparser.consolePrintln(y.getArgumentName() + " = " + y.getArgumentValue());
y = new Argument("y","sin(y)-z", y, z);
mXparser.consolePrintln(y.getArgumentName() + " = " + y.getArgumentValue());
/* syntax checking */
y.setArgumentExpressionString("n*sin(y)-z");
mXparser.consolePrintln(y.getArgumentName() + " = ... \n syntax = " + y.checkSyntax() + "\n message = \n" + y.getErrorMessage());
y.addArguments(n);
mXparser.consolePrintln(y.getArgumentName() + " = ... \n syntax = " + y.checkSyntax() + "\n message = \n" + y.getErrorMessage());
mXparser.consolePrintln(y.getArgumentName() + " = " + y.getArgumentValue());
/*
* the same methods could be called
* for the expression syntax checking
*
*/
/*
* Complex expressions
*/
/*
* Summation operator SIGMA
* sum(index, from, to, expr)
* sum(index, from, to, expr, by)
*
*/
Expression e16 = new Expression("sum(i,1,10,i)");
mXparser.consolePrintln(e16.getExpressionString() + " = " + e16.calculate());
Expression e17 = new Expression("sum(i,1,10,i,0.5)");
mXparser.consolePrintln(e17.getExpressionString() + " = " + e17.calculate());
/*
* Product operator SIGMA
* prod(index, from, to, expr)
* prod(index, from, to, expr, by)
*/
/* factorial */
Expression e18 = new Expression("prod(i,1,5,i)");
mXparser.consolePrintln(e18.getExpressionString() + " = " + e18.calculate());
Expression e19 = new Expression("prod(i,1,5,i,0.5)");
mXparser.consolePrintln(e19.getExpressionString() + " = " + e19.calculate());
/* Approximation sin(x) by Taylor series
* ! - factorial
*/
Expression e20 = new Expression("sin(x)-sum(n,0,10,(-1)^n*(x^(2*n+1))/(2*n+1)!)", x);
x.setArgumentValue(1);
mXparser.consolePrintln("x = " + x.getArgumentValue() + ", " + e20.getExpressionString() + " = " + e20.calculate());
x.setArgumentValue(5);
mXparser.consolePrintln("x = " + x.getArgumentValue() + ", " + e20.getExpressionString() + " = " + e20.calculate());
x.setArgumentValue(10);
mXparser.consolePrintln("x = " + x.getArgumentValue() + ", " + e20.getExpressionString() + " = " + e20.calculate());
/*
* calculating pi by integral of
* sqrt(1-x^2) from -1 to 1
* using simple summation operator
*/
Argument d = new Argument("d",0.1);
Expression e21 = new Expression("2*sum(x, -1, 1, d*sqrt(1-x^2), d)", d);
mXparser.consolePrintln("d = " + d.getArgumentValue() + ", " + e21.getExpressionString() + " = " + e21.calculate());
d.setArgumentValue(0.01);
mXparser.consolePrintln("d = " + d.getArgumentValue() + ", " + e21.getExpressionString() + " = " + e21.calculate());
/*
* Derivatives
*
* der( f(x,...), x) - general
* der+( f(x,...), x) - right
* der-( f(x,...), x) - left
*/
/* cos(x) as derivative from sin(x) */
Expression e22 = new Expression("cos(x)-der(sin(x), x)", x);
mXparser.consolePrintln(e22.getExpressionString() + " = " + e22.calculate());
/* left and right derivative from |x| */
x.setArgumentValue(0);
Expression e23 = new Expression("der-(abs(x), x)", x);
mXparser.consolePrintln("x = " + x.getArgumentValue() + ", " + e23.getExpressionString() + " = " + e23.calculate());
Expression e24 = new Expression("der+(abs(x), x)", x);
mXparser.consolePrintln("x = " + x.getArgumentValue() + ", " + e24.getExpressionString() + " = " + e24.calculate());
/* derivative from sin(x) as Taylor series (approximation) */
x.setArgumentValue(1);
Expression e25 = new Expression("cos(x)-der(sum(n,0,10,(-1)^n*(x^(2*n+1))/(2*n+1)!), x)", x);
x.setArgumentValue(1);
mXparser.consolePrintln("x = " + x.getArgumentValue() + ", " + e25.getExpressionString() + " = " + e25.calculate());
x.setArgumentValue(5);
mXparser.consolePrintln("x = " + x.getArgumentValue() + ", " + e25.getExpressionString() + " = " + e25.calculate());
x.setArgumentValue(10);
mXparser.consolePrintln("x = " + x.getArgumentValue() + ", " + e25.getExpressionString() + " = " + e25.calculate());
/*
* Integral
* int(f(x,...), x, a, b)
*/
/* calculating PI value */
Expression e26 = new Expression("2*int(sqrt(1-x^2), x, -1, 1)");
mXparser.consolePrintln(e26.getExpressionString() + " = " + e26.calculate());
/*
* Parser constants
*/
Expression e27 = new Expression("pi");
mXparser.consolePrintln(e27.getExpressionString() + " = " + e27.calculate());
Expression e28 = new Expression("e");
mXparser.consolePrintln(e28.getExpressionString() + " = " + e28.calculate());
/* and many many more ... */
/*
* USER DEFINED FUNCTIONS
* f(x,y) = sin(x+y)
* f(a,b,c,d,...) = ....
*/
Function f = new Function("f", "x^2", "x");
Expression e29 = new Expression("f(2)");
e29.addFunctions(f);
mXparser.consolePrintln(e29.getExpressionString() + " = " + e29.calculate());
/*
* Please be informed that sequence of
* arguments names is important. In the below exampe
* a - 1st argument of f
* b - 2nd argument of f
* c - 3rd argument of f
*
* In the expressions f will be c alled as f( . , . , . )
*/
f = new Function("f", "a+b+c", "a", "b", "c");
Expression e30 = new Expression("f(1, 2, 3)");
e30.addFunctions(f);
mXparser.consolePrintln(e30.getExpressionString() + " = " + e30.calculate());
/*
* Using functions in functions
*/
f = new Function("f", "x^2", "x");
Function g = new Function("g", "f(x)^2", "x");
g.addFunctions(f);
mXparser.consolePrintln("g(2) = " + g.calculate(2));
Expression e31 = new Expression("f(x)+g(2*x)", x);
e31.addFunctions(f, g);
mXparser.consolePrintln("x = " + x.getArgumentValue() + ", " + e31.getExpressionString() + " = " + e31.calculate());
x.setArgumentValue(2);
Expression e32 = new Expression("der(g(x),x)", x);
e32.addFunctions(g);
mXparser.consolePrintln("x = " + x.getArgumentValue() + ", " + e32.getExpressionString() + " = " + e32.calculate());
/*
* Fundamental theorem of calculus
* if F(x) = int_a^x f(t) dt
* then F'(x) = f(x)
*/
f = new Function("f", "sin(x)", "x");
Function F = new Function("F", "int(f(t), t, 0, x)", "x");
F.addFunctions(f);
Expression e33 = new Expression("f(x) - der(F(x),x)", x);
e33.addFunctions(f, F);
mXparser.consolePrintln("x = " + x.getArgumentValue() + ", " + e33.getExpressionString() + " = " + e33.calculate() +
", computing time : " + e33.getComputingTime() + " s.");
/*
* Simple (fast) recursion
* Only one index n >= 0, n integer
*/
/* Fibonacci numbers with add base cases method*/
n = new Argument("n");
RecursiveArgument fib1 = new RecursiveArgument("fib1", "fib1(n-1)+fib1(n-2)", n);
fib1.addBaseCase(0, 0);
fib1.addBaseCase(1, 1);
mXparser.consolePrintln("fib1: ");
for (int i = 0; i <= 10; i++ )
mXparser.consolePrint(fib1.getArgumentValue(i) + ", ");
mXparser.consolePrintln();
/* Fibonacci numbers with if statement*/
RecursiveArgument fib2 = new RecursiveArgument("fib2", "if( n>1, fib2(n-1)+fib2(n-2), if(n=1,1,0) )", n);
mXparser.consolePrintln("fib2: ");
for (int i = 0; i <= 10; i++ )
mXparser.consolePrint(fib2.getArgumentValue(i) + ", ");
mXparser.consolePrintln();
Expression e34 = new Expression("sum(i, 0, 10, fib1(i))", fib1);
mXparser.consolePrintln(e34.getExpressionString() + " = " + e34.calculate() +
", computing time : " + e34.getComputingTime() + " s.");
Expression e35 = new Expression("sum(i, 0, 10, fib2(i))", fib2);
mXparser.consolePrintln(e35.getExpressionString() + " = " + e35.calculate() +
", computing time : " + e35.getComputingTime() + " s.");
/*
* Complex recursion (slow)
* any definition
*
*
*/
/* Fibonacci numbers using complex recursion */
Function fib3 = new Function("fib3","if(n>1, fib3(n-1)+fib3(n-2), if(n>0,1,0))", "n");
mXparser.consolePrintln("fib2: ");
for (int i = 0; i <= 10; i++ )
mXparser.consolePrint(fib3.calculate(i) + ", ");
mXparser.consolePrintln();
Expression e36 = new Expression("sum(i, 0, 10, fib3(i))");
e36.addFunctions(fib3);
mXparser.consolePrintln(e36.getExpressionString() + " = " + e36.calculate() +
", computing time : " + e36.getComputingTime() + " s.");
/*
* Chebyshev polynomials definition using
* recursive functions
*/
Function T = new Function("T","if(n>1, 2*x*T(n-1,x)-T(n-2,x), if(n>0, x, 1) )", "n", "x");
Argument k = new Argument("k", 5);
Expression e37 = new Expression("T(k,x) - ( (x + sqrt(x^2-1))^k + (x - sqrt(x^2-1))^k)/2", k, x);
e37.addFunctions(T);
mXparser.consolePrintln(e37.getExpressionString() + " = " + e37.calculate() +
", computing time : " + e37.getComputingTime() + " s.");
/*
* Binomial coefficient using complex recursion
*/
Function Cnk = new Function("Cnk","if( k>0, if( k<n, Cnk(n-1,k-1)+Cnk(n-1,k), 1), 1)","n", "k");
Expression e38 = new Expression("C(10,5) - Cnk(10,5)");
e38.addFunctions(Cnk);
mXparser.consolePrintln(e38.getExpressionString() + " = " + e38.calculate() +
", computing time : " + e38.getComputingTime() + " s.");
/*
* Differences between simple and complex recursion
*
* Simple:
*
* Advantages
* 1) fast
* 2) remembers what was previously calculated
* 3) calculations are done in a controlled way
* - recursion counter (each recursion step increases
* recursion counter, for calculating n-th recursion
* value maximum n recursion steps are needed
* - no negative indexes
* 4) add base value method
*
* Disadvantages
* 1) limited to one index argument (positive integer index argument)
*
* Complex recursion
*
* Advantages
* 1) flexible - no limitations
*
* Disadvantages
* 1) slow
* 2) no add base values method
*/
/*
* User defined constants
*/
Constant a = new Constant("a", 5);
Constant b = new Constant("b", 10);
Constant c = new Constant("c", 15);
Expression e39 = new Expression("a+b+c");
e39.addConstants(a, b, c);
/*
* For example in verbose mode
* computing
*/
e39.setVerboseMode();
e39.checkSyntax();
mXparser.consolePrintln();
mXparser.consolePrintln(e39.getErrorMessage());
mXparser.consolePrintln(e39.getExpressionString() + " = " + e39.calculate() +
", computing time : " + e39.getComputingTime() + " s.");
/*
* There are much more other features in the mXparser API.
* Please refer to the API specifications.
*
* Please be aware that this is the version 1.0 of the parser
* - I am pretty sure you will find some bugs - if so please send me
* more info: [email protected]
*/
}