# Difference between revisions of "Mathematical functions"

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* ''board.I(interval,f)'': Numerically computed v alue integral of the function ''f'' in the given interval. | * ''board.I(interval,f)'': Numerically computed v alue integral of the function ''f'' in the given interval. | ||

* ''board.root(f,x)'': root of the function f. Uses Newton method with start value ''x''. | * ''board.root(f,x)'': root of the function f. Uses Newton method with start value ''x''. | ||

− | * ''board.factorial(n)'': computes <math>n! = n\cdot(n-1)\ | + | * ''board.factorial(n)'': computes <math>n! = n\cdot(n-1)\cdots2\cdot 1</math>. |

* ''board.lagrangePolynomial(p)'': returns a function which describes the Lagrange polynomial through the points in the array ''p''. | * ''board.lagrangePolynomial(p)'': returns a function which describes the Lagrange polynomial through the points in the array ''p''. |

## Revision as of 21:10, 30 January 2009

## Functions of the JavaScript Object Math

The following functions are part of every JavaScript virtual machine:

*Math.abs*;*Math.acos*;*Math.asin*;*Math.atan*;*Math.ceil*;*Math.cos*;*Math.exp*;*Math.floor*;*Math.log*;*Math.max*;*Math.min*;*Math.random*;*Math.sin*;*Math.sqrt*;*Math.tan*;

JSXGraph expands the set of available mathematical functions. To keep the JavaScript implementations clean, the new mathematical functions are part of the JSXGraph board. That means, initially a board has to be created, for example with the command

```
board = JXG.JSXGraph.initBoard('box', {originX: 250, originY: 250, unitX: 40, unitY: 40});
```

Then, the object *board* contains the following additional mathematical functions:

*board.angle(A, B, C)*: for Point objects A, B, C. (A: name string, id string or object pointer)*board.rad(A, B, C)**board.distance(arr1, arr2)*: Euclidean distane between two vectors*board.pow(a, b)*: [math]a^b[/math] for floating point value of*b*. Math.pow is defined for integer values of*b', only.**board.round(x, n)*: returns string with fixed point representation of*x*. It is aa wrapper for string.tofixed(n).*board.cosh(x)**board.sinh(x)**board.D(f)*: Numerically computed derivative of the function*f*, returns a function.*board.I(interval,f)*: Numerically computed v alue integral of the function*f*in the given interval.*board.root(f,x)*: root of the function f. Uses Newton method with start value*x*.*board.factorial(n)*: computes [math]n! = n\cdot(n-1)\cdots2\cdot 1[/math].*board.lagrangePolynomial(p)*: returns a function which describes the Lagrange polynomial through the points in the array*p*.