API Docs for: 0.99.4
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Functiongraph Class

PSEUDO

Extends JXG.Curve
Module: JXG

This element is used to provide a constructor for functiongraph, which is just a wrapper for element Curve with undefined set to x. The graph is drawn for x in the interval [a,b].

Constructor

Functiongraph

(
  • f,a_,b_
)

Parameters:

  • f,a_,b_ Function_number,function_number,function

    Parent elements are a function term f(x) describing the function graph.

    Further, an optional number or function for the left interval border a, and an optional number or function for the right interval border b.

    Default values are a=-10 and b=10.

See also:

Example:

// Create a function graph for f(x) = 0.5*x*x-2*x
        var graph = board.create('functiongraph',
                           [function(x){ return 0.5*x*x-2*x;}, -2, 4]
                        );
        
// Create a function graph for f(x) = 0.5*x*x-2*x with variable interval
        var s = board.create('slider',[[0,4],[3,4],[-2,4,5]]);
        var graph = board.create('functiongraph',
                           [function(x){ return 0.5*x*x-2*x;},
                            -2,
                            function(){return s.Value();}]
                        );
        

Item Index

Methods

_borderCase

(
  • a
  • b
  • c
  • ta
  • tb
  • tc
  • depth
)
JXG.Boolean private

Investigate a function term at the bounds of intervals where the function is not defined, e.g. log(x) at x = 0.

c is between a and b

Parameters:

  • a Array

    Screen coordinates of the left interval bound

  • b Array

    Screen coordinates of the right interval bound

  • c Array

    Screen coordinates of the bisection point at (ta + tb) / 2

  • ta Number

    Parameter which evaluates to a, i.e. [1, X(ta), Y(ta)] = a in screen coordinates

  • tb Number

    Parameter which evaluates to b, i.e. [1, X(tb), Y(tb)] = b in screen coordinates

  • tc Number

    (ta + tb) / 2 = tc. Parameter which evaluates to b, i.e. [1, X(tc), Y(tc)] = c in screen coordinates

  • depth Number

    Actual recursion depth. The recursion stops if depth is equal to 0.

Returns:

JXG.Boolean:

true if the point is inserted and the recursion should stop, false otherwise.

_insertPoint

(
  • pnt
)
private

Add a point to the curve plot. If the new point is too close to the previously inserted point, it is skipped. Used in undefined.

Parameters:

  • pnt JXG.Coords

    Coords to add to the list of points

_isOutside

(
  • a
  • ta
  • b
  • tb
)
Boolean private

Determines if a segment is outside of the visible canvas (plus a certain border).

Parameters:

  • a Number

    First point of the segement

  • ta Number

    Parameter of the curve for first point

  • b Number

    Second point of the segment

  • tb Number

    Parameter of the curve for second point

Returns:

Boolean:

True if segment is visible.

_isUndefined

(
  • a
  • ta
  • b
  • tb
)
private

Test if the function is undefined on an interval: If the interval borders a and b are undefined, 20 random values are tested if they are undefined, too. Only if all values are undefined, we declare the function to be undefined in this interval.

Parameters:

  • a Array

    Screen coordinates of the left interval bound

  • ta Number

    Parameter which evaluates to a, i.e. [1, X(ta), Y(ta)] = a in screen coordinates

  • b Array

    Screen coordinates of the right interval bound

  • tb Number

    Parameter which evaluates to b, i.e. [1, X(tb), Y(tb)] = b in screen coordinates

_plotRecursive

(
  • a
  • ta
  • b
  • tb
  • depth
  • delta
)
JXG.Curve private chainable

Recursive interval bisection algorithm for curve plotting. Used in undefined.

Parameters:

  • a Array

    Screen coordinates of the left interval bound

  • ta Number

    Parameter which evaluates to a, i.e. [1, X(ta), Y(ta)] = a in screen coordinates

  • b Array

    Screen coordinates of the right interval bound

  • tb Number

    Parameter which evaluates to b, i.e. [1, X(tb), Y(tb)] = b in screen coordinates

  • depth Number

    Actual recursion depth. The recursion stops if depth is equal to 0.

  • delta Number

    If the distance of the bisection point at (ta + tb) / 2 from the point (a + b) / 2 is less then delta, the segment [a,b] is regarded as straight line.

Returns:

JXG.Curve:

Reference to the curve object.

_set

(
  • property
  • value
)
private chainable
Sets the value of property property to value.

Parameters:

  • property String
    The property's name.
  • value Object
    The new value

_triangleDists

(
  • a
  • b
  • c
)
Array private

Compute distances in screen coordinates between the points ab, ac, cb, and cd, where d = (a + b)/2. cd is used for the smoothness test, ab, ac, cb are used to detect jumps, cusps and poles.

Parameters:

  • a Array

    Screen coordinates of the left interval bound

  • b Array

    Screen coordinates of the right interval bound

  • c Array

    Screen coordinates of the bisection point at (ta + tb) / 2

Returns:

Array:

array of distances in screen coordinates between: ab, ac, cb, and cd.

addChild

(
  • obj
)
chainable
Add an element as a child to the current element. Can be used to model dependencies between geometry elements.

Parameters:

addDescendants

(
  • obj
)
private chainable
Adds the given object to the descendants list of this object and all its child objects.

Parameters:

addParents

(
  • parents
)
JXG.Object chainable
Adds ids of elements to the array this.parents. This method needs to be called if some dependencies can not be detected automatically by JSXGraph. For example if a function graph is given by a function which referes to coordinates of a point, calling addParents() is necessary.

Parameters:

  • parents Array
    Array of elements or ids of elements. Alternatively, one can give a list of objects as parameters.

Returns:

JXG.Object: reference to the object itself.

Example:

// Movable function graph
                    var A = board.create('point', [1, 0], {name:'A'}),
                        B = board.create('point', [3, 1], {name:'B'}),
                        f = board.create('functiongraph', function(x) {
                                 var ax = A.X(),
                                     ay = A.Y(),
                                     bx = B.X(),
                                     by = B.Y(),
                                    a = (by - ay) / ( (bx - ax) * (bx - ax) );
                                 return a * (x - ax) * (x - ax) + ay;
                             }, {fixed: false});
                    f.addParents([A, B]);
                    

addRotation

(
  • angle
)
chainable
Rotate texts or images by a given degree. Works only for texts where JXG.Text#display equal to "internal".

Parameters:

  • angle Number
    The degree of the rotation (90 means vertical text).

See also:

  • JXG.GeometryElement#rotate

addTransform

(
  • transform
)
JXG.Curve chainable

Inherited from JXG.GeometryElement but overwritten in src/base/curve.js:1172

Add transformations to this curve.

Parameters:

  • transform JXG.Transformation | Array

    Either one {@link JXG.Transformation} or an array of {@link JXG.Transformation}s.

Returns:

JXG.Curve:

Reference to the curve object.

allocatePoints

() private chainable

Allocate points in the Coords array this.points

animate

(
  • hash
  • time
  • [options]
)
JXG.GeometryElement chainable
Animates properties for that object like stroke or fill color, opacity and maybe even more later.

Parameters:

  • hash Object
    Object containing properties with target values for the animation.
  • time Number
    Number of milliseconds to complete the animation.
  • [options] Object optional
    Optional settings for the animation:
    • callback: A function that is called as soon as the animation is finished.

Returns:

JXG.GeometryElement: A reference to the object

bounds

() Array
Dimensions of the smallest rectangle enclosing the element.

Returns:

Array:

The coordinates of the enclosing rectangle in a format like the bounding box in {@link JXG.Board#setBoundingBox}.

checkReal

() JXG.Curve private chainable

Check if at least one point on the curve is finite and real and sets the property isReal.

Returns:

JXG.Curve:

Reference to the curve object.

clearTrace

() chainable
Removes all objects generated by the trace function.

cloneToBackground

() chainable
Copy the element to background. This is used for tracing elements.

countChildren

() Number private
Counts the direct children of an object without counting labels.

Returns:

Number: Number of children

createGradient

() private chainable
Creates a gradient nodes in the renderer.

See also:

  • JXG.SVGRenderer#setGradient

createLabel

() chainable
Creates a label element for this geometry element.

See also:

  • #addLabelToElement

dash

(
  • d
)
deprecated chainable

Inherited from JXG.GeometryElement: src/base/element.js:1703

Deprecated: Use {@link #setAttribute}

Set the dash type of an element

Parameters:

  • d Number
    Integer which determines the way of dashing an element's outline.

See also:

draggable

() Boolean private
Decides whether an element can be dragged. This is used in {{#crossLink "JXG.GeometryElement/setPositionDirectly:method"}}JXG.GeometryElement#setPositionDirectly{{/crossLink}} methods where all parent elements are checked if they may be dragged, too.

Returns:

fillColor

(
  • fColor
)
deprecated chainable

Inherited from JXG.GeometryElement: src/base/element.js:1657

Deprecated: Use {@link #setAttribute}

Set the fillColor of an element

Parameters:

  • fColor String
    String which determines the fill color of an object.

See also:

generatePolynomial

() Array
Array of strings containing the polynomials defining the element. Used for determining geometric loci the groebner way.

Returns:

Array:

An array containing polynomials describing the locus of the current object.

generateTerm

(
  • varname
  • xterm
  • yterm
  • mi
  • ma
)
JXG.Curve chainable

Converts the GEONExT syntax of the defining function term into JavaScript. New methods X() and Y() for the Curve object are generated, further new methods for minX() and maxX().

Parameters:

Returns:

JXG.Curve:

Reference to the curve object.

See also:

  • JXG.Curve#JXG.GeonextParser.geonext2JS.

getAttribute

(
  • key
)
Get the value of the property key.

Parameters:

  • key String
    The name of the property you are looking for

Returns:

The value of the property

getAttributes

() Object
Retrieve a copy of the current visProp.

Returns:

getLabelAnchor

() JXG.Coords
Returns the coords object where the label of the element shall be drawn. Differs in some cases from the values that getTextAnchor returns.

Returns:

JXG.Coords: JXG.Coords Place where the text shall be drawn.

See also:

getName

() String
Returns the elements name, used in JessieCode.

Returns:

getParents

() Array
List of the element ids resp. values used as parents in {{#crossLink "JXG.Board/create:method"}}JXG.Board#create{{/crossLink}}.

Returns:

getProperty

() deprecated

Inherited from JXG.GeometryElement: src/base/element.js:1237

Deprecated: Use {@link JXG.GeometryElement#getAttribute}.

Deprecated alias for {{#crossLink "JXG.GeometryElement/getAttribute:method"}}JXG.GeometryElement#getAttribute{{/crossLink}}.

getTextAnchor

() JXG.Coords
Returns the coords object where a text that is bound to the element shall be drawn. Differs in some cases from the values that getLabelAnchor returns.

Returns:

JXG.Coords: JXG.Coords Place where the text shall be drawn.

See also:

getTpye

() String
The type of the element as used in {{#crossLink "JXG.Board/create:method"}}JXG.Board#create{{/crossLink}}.

Returns:

handleSnapToGrid

(
  • force
)
JXG.GeometryElement chainable
Move an element to its nearest grid point. The function uses the coords object of the element as its actual position. If there is no coords object, nothing is done.

Parameters:

  • force Boolean
    force snapping independent from what the snaptogrid attribute says

Returns:

JXG.GeometryElement: Reference to this element

hasPoint

(
  • x
  • y
  • start
)
Boolean

Inherited from JXG.GeometryElement but overwritten in src/base/curve.js:194

Checks whether (x,y) is near the curve.

Parameters:

  • x Number

    Coordinate in x direction, screen coordinates.

  • y Number

    Coordinate in y direction, screen coordinates.

  • start Number

    Optional start index for search on data plots.

Returns:

Boolean:

True if (x,y) is near the curve, False otherwise.

hideElement

() chainable
Hide the element. It will still exist but not visible on the board.

highlight

(
  • [force=false]
)
chainable
Highlights the element.

Parameters:

  • [force=false] Boolean optional
    Force the highlighting

highlightFillColor

(
  • fColor
)
deprecated chainable

Inherited from JXG.GeometryElement: src/base/element.js:1673

Deprecated: Use {@link #setAttribute}

Set the highlightFillColor of an element

Parameters:

  • fColor String
    String which determines the fill color of an object when its highlighted.

See also:

highlightStrokeColor

(
  • sColor
)
deprecated chainable

Inherited from JXG.GeometryElement: src/base/element.js:1611

Deprecated: Use {@link #setAttribute}

Set the highlightStrokeColor of an element

Parameters:

  • sColor String
    String which determines the stroke color of an object when its highlighted.

See also:

interpolationFunctionFromArray

(
  • which
)
Function private

Generate the method curve.X() in case curve.dataX is an array and generate the method curve.Y() in case curve.dataY is an array.

Parameters:

  • which String

    Either 'X' or 'Y'

Returns:

isDistOK

(
  • dx
  • dy
  • MAXX
  • MAXY
)
Boolean private

Compares the absolute value of dx with MAXX and the absolute value of dy with MAXY.

Parameters:

Returns:

Boolean:

true, if |dx| < MAXX and |dy| < MAXY.

isSegmentDefined

() private

isSegmentOutside

(
  • x0
  • y0
  • x1
  • y1
)
Boolean private

Crude and cheap test if the segment defined by the two points (x0, y0) and (x1, y1) is outside the viewport of the board. All parameters have to be given in screen coordinates.

Parameters:

Returns:

Boolean:

true if the given segment is outside the visible area.

labelColor

(
  • lColor
)
deprecated chainable

Inherited from JXG.GeometryElement: src/base/element.js:1688

Deprecated: Use {@link #setAttribute}

Set the labelColor of an element

Parameters:

  • lColor String
    String which determines the text color of an object's label.

See also:

maxX

() Number

Gives the default value of the right bound for the curve. May be overwritten in JXG.Curve#generateTerm.

Returns:

Number:

Right bound for the curve.

minX

() Number

Gives the default value of the left bound for the curve. May be overwritten in JXG.Curve#generateTerm.

Returns:

Number:

Left bound for the curve.

noHighlight

() chainable
Uses the "normal" properties of the element.

normalize

() private chainable
Normalize the element's standard form.

notifyParents

(
  • contentStr
)
JXG.Curve chainable

Finds dependencies in a given term and notifies the parents by adding the dependent object to the found objects child elements.

Parameters:

  • contentStr String

    String containing dependencies for the given object.

Returns:

JXG.Curve:

Reference to the curve object.

prepareUpdate

() private chainable
Notify all child elements for updates.

remove

() chainable
Removes the element from the construction. This only removes the SVG or VML node of the element and its label (if available) from the renderer, to remove the element completely you should use {{#crossLink "JXG.Board/removeObject:method"}}JXG.Board#removeObject{{/crossLink}}.

removeChild

(
  • obj
)
chainable
Remove an element as a child from the current element.

Parameters:

removeDescendants

(
  • obj
)
private chainable
Removes the given object from the descendants list of this object and all its child objects.

Parameters:

resolveShortcuts

(
  • properties
)
Object
Resolves property shortcuts like color and expands them, e.g. strokeColor and fillColor. Writes the expanded properties back to the given properties.

Parameters:

Returns:

Object: The given parameter with shortcuts expanded.

setArrow

(
  • firstArrow
  • lastArrow
)
chainable
Determines whether the element has arrows at start or end of the arc.

Parameters:

  • firstArrow Boolean
    True if there is an arrow at the start of the arc, false otherwise.
  • lastArrow Boolean
    True if there is an arrow at the end of the arc, false otherwise.

setAttribute

(
  • attributes
)
chainable
Sets an arbitrary number of attributes.

Parameters:

  • attributes Object
    An object with attributes.

Example:

// Set property directly on creation of an element using the attributes object parameter
                    var board = JXG.JSXGraph.initBoard('jxgbox', {boundingbox: [-1, 5, 5, 1]};
                    var p = board.create('point', [2, 2], {visible: false});
                    
                    // Now make this point visible and fixed:
                    p.setAttribute({
                        fixed: true,
                        visible: true
                    });

setDash

(
  • dash
)
private chainable
Set the dash style of an object. See undefined for a list of available dash styles. You should use undefined instead of this method.

Parameters:

  • dash Number
    Indicates the new dash style

setLabel

(
  • str
)
chainable
Sets a label and it's text If label doesn't exist, it creates one

Parameters:

setLabelText

(
  • str
)
chainable
Updates the element's label text, strips all html.

Parameters:

setName

(
  • str
)
chainable
Updates the element's label text and the element's attribute "name", strips all html.

Parameters:

setParents

(
  • parents
)
JXG.Object chainable
Sets ids of elements to the array this.parents. First, this.parents is cleared. See undefined.

Parameters:

  • parents Array
    Array of elements or ids of elements. Alternatively, one can give a list of objects as parameters.

Returns:

JXG.Object: reference to the object itself.

setPosition

(
  • method
  • coords
)
JXG.GeometryElement chainable
Translates the object by (x, y). In case the element is defined by points, the defining points are translated, e.g. a circle constructed by a center point and a point on the circle line.

Parameters:

  • method Number

    The type of coordinates used here. Possible values are {@link JXG.COORDS_BY_USER} and {@link JXG.COORDS_BY_SCREEN}.

  • coords Array

    array of translation vector.

Returns:

JXG.GeometryElement:

Reference to the element object.

setPositionDirectly

(
  • method
  • coords
  • oldcoords
)
JXG.GeometryElement chainable
Moves an by the difference of two coordinates.

Parameters:

  • method Number

    The type of coordinates used here. Possible values are {@link JXG.COORDS_BY_USER} and {@link JXG.COORDS_BY_SCREEN}.

  • coords Array

    coordinates in screen/user units

  • oldcoords Array

    previous coordinates in screen/user units

Returns:

JXG.GeometryElement:

this element

setProperty

() deprecated

Inherited from JXG.GeometryElement: src/base/element.js:1030

Deprecated: Use {@link JXG.GeometryElement#setAttribute}.

Deprecated alias for {{#crossLink "JXG.GeometryElement/setAttribute:method"}}JXG.GeometryElement#setAttribute{{/crossLink}}.

shadow

(
  • s
)
deprecated chainable

Inherited from JXG.GeometryElement: src/base/element.js:1733

Deprecated: Use {@link #setAttribute}

Set the shadow of an element

Parameters:

  • s Boolean
    Boolean which determines whether the element has a shadow or not.

See also:

showElement

() chainable
Make the element visible.

snapToGrid

() JXG.GeometryElement chainable
Snaps the element to the grid. Only works for points, lines and circles. Points will snap to the grid as defined in their properties undefined and undefined. Lines and circles will snap their parent points to the grid, if they have undefined set to true.

Returns:

JXG.GeometryElement: Reference to the element.

snapToPoints

() JXG.GeometryElement chainable
Snaps the element to points. Only works for points. Points will snap to the next point as defined in their properties undefined and undefined. Lines and circles will snap their parent points to points.

Returns:

JXG.GeometryElement: Reference to the element.

strokeColor

(
  • sColor
)
deprecated chainable

Inherited from JXG.GeometryElement: src/base/element.js:1626

Deprecated: Use {@link #setAttribute}

Set the strokeColor of an element

Parameters:

  • sColor String
    String which determines the stroke color of an object.

See also:

strokeWidth

(
  • width
)
deprecated chainable

Inherited from JXG.GeometryElement: src/base/element.js:1641

Deprecated: Use {@link #setAttribute}

Set the strokeWidth of an element

Parameters:

  • width Number
    Integer which determines the stroke width of an outline.

See also:

toJSON

() private
EXPERIMENTAL. Generate JSON object code of visProp and other properties.

Returns:

JSON string containing element's properties.

update

() JXG.Curve chainable

Inherited from JXG.GeometryElement but overwritten in src/base/curve.js:327

Computes for equidistant points on the x-axis the values of the function

Returns:

JXG.Curve:

Reference to the curve object.

See also:

updateCurve

() JXG.Curve chainable

Computes the path of coordinates defining the curve. For this various methods are used, depending whether the curve is defined by a data array of by function terms. If the mousemove event triggers this update, we use only few points. Otherwise, e.g. on mouseup, many points are used.

Returns:

JXG.Curve:

Reference to the curve object.

updateDataArray

()

For dynamic dat aplots, updateDataArray can be used to compute new entries for the arrays JXG.Curve#dataX and JXG.Curve#dataY. It is used in JXG.Curve#updateCurve. Default is an empty method, can be overwritten by the user.

Example:

In this example the filled curve which shows the intersection of two polygons is plotted. The curve is defined by the coordinates in dataX and dataY.

var i,
                        board = JXG.JSXGraph.initBoard('box', {boundingbox: [-8,8,8,-8], axis: true}),
                        pts1 = [[-2, 3], [-4, -3], [2, 0], [4, 4]],
                        pts2 = [[-2, -3], [-4, 1], [0, 4], [5, 1]];
                    
                    // Clipping polygon
                    var pol = board.create('polygon', pts1,
                                {hasInnerPoints: true,
                                 borders: {names: ['', '', '', '']},
                                 name:'Polygon1', withLabel: true, visible: true,
                                 fillColor: 'yellow'});
                    
                    // Polygon to be clipped
                    var pol2 = board.create('polygon', pts2,
                                {hasInnerPoints: false,
                                 borders: {names: ['', '', '', '']},
                                 name:'Polygon2', withLabel: true, visible: true
                                 });
                    
                    var curve = board.create('curve', [[],[]], {fillColor: 'blue', fillOpacity: 0.4});
                    curve.updateDataArray = function() {
                        var mat = JXG.Math.transpose(pol.intersect(pol2));
                    
                        if (mat.length == 3) {
                            this.dataX = mat[1];
                            this.dataY = mat[2];
                        } else {
                            this.dataX = [];
                            this.dataY = [];
                        }
                    
                    };
                    
                    board.update();
                    

updateParametricCurve

(
  • mi
  • ma
)
JXG.Curve chainable

Updates the data points of a parametric curve. This version is used if undefined is true.

Parameters:

  • mi Number

    Left bound of curve

  • ma Number

    Right bound of curve

Returns:

JXG.Curve:

Reference to the curve object.

updateParametricCurveNaive

(
  • mi
  • ma
  • len
)
JXG.Curve chainable

Updates the data points of a parametric curve using a fixed set of equidistant points. This version is used if undefined is false.

Parameters:

  • mi Number

    Left bound of curve

  • ma Number

    Right bound of curve

  • len Number

    Number of data points

Returns:

JXG.Curve:

Reference to the curve object.

updateParametricCurveOld

(
  • mi
  • ma
)
JXG.Curve deprecated chainable

Updates the data points of a parametric curve. This version is used if undefined is true. Since 0.99 this algorithm is deprecated. It still can be used if undefined is true.

Parameters:

  • mi Number

    Left bound of curve

  • ma Number

    Right bound of curve

Returns:

JXG.Curve:

Reference to the curve object.

updateRenderer

() private chainable
Provide updateRenderer method.

updateTransform

(
  • p
)
JXG.Point

Applies the transformations of the curve to the given point p. Before using it, JXG.Curve#updateTransformMatrix has to be called.

Parameters:

Returns:

JXG.Point:

The given point.

updateTransformMatrix

() JXG.Curve private chainable

Update the transfomration matrices bound to this curve.

Returns:

JXG.Curve:

Reference to the curve object.

visible

(
  • v
)
deprecated chainable

Inherited from JXG.GeometryElement: src/base/element.js:1718

Deprecated: Use {@link #setAttribute}

Set the visibility of an element

Parameters:

  • v Boolean
    Boolean which determines whether the element is drawn.

See also:

Z

(
  • t
)
Number

Treat the curve as curve with homogeneous coordinates.

Parameters:

  • t Number

    A number between 0.0 and 1.0.

Returns:

Number:

Always 1.0

Properties

_org_type

Number final
Original type of the element at construction time. Used for removing glider property.

_pos

Number private
The position of this element inside the undefined.

Default: -1

ancestors

Object
Elements on which this element depends on are stored here.

baseElement

JXG.GeometryElement private

Default: null

board

JXG.Board
Reference to the board associated with the element.

childElements

Object
Stores all dependent objects to be updated when this point is moved.

descendants

Object
Elements depending on this element are stored here.

dump

Boolean
The element is saved with an explicit entry in the file (true) or implicitly via a composition.

Default: true

elementClass

Number final
The element's class.

elType

String
The string used with {{#crossLink "JXG.Board/create:method"}}JXG.Board#create{{/crossLink}}

hasLabel

Boolean
If element has a label subelement then this property will be set to true.

Default: false

highlighted

Boolean
True, if the element is currently highlighted.

Default: false

id

String
Unique identifier for the element. Equivalent to id-attribute of renderer element.

isDraggable

Boolean
Controls if this element can be dragged. In GEONExT only free points and gliders can be dragged.

Default: false

isReal

Boolean
If element is in two dimensional real space this is true, else false.

Default: true

lastDragTime

Date
Time stamp containing the last time this element has been dragged.

Default: creation time

methodMap

Object
The methodMap determines which methods can be called from within JessieCode and under which name it can be used. The map is saved in an object, the name of a property is the name of the method used in JessieCode, the value of a property is the name of the method in JavaScript.

mouseover

Boolean
Is the mouse over this element?

Default: false

name

String
Not necessarily unique name for the element.

Default: Name generated by {@link JXG.Board#generateName}.

See also:

needsUpdate

Boolean
Controls if updates are necessary

Default: true

notExistingParents

Object
Stores all Intersection Objects which in this moment are not real and so hide this element.

numberPoints

Number

Number of points on curves when plotted with updateParametricCurveNaive. This value changes between the attribute values numberPointsLow and numberPointsHigh. The first value is taken during drag events, the latter one is taken in the up event. It is set in JXG.Curve#updateCurve.

numTraces

Number
Counts the number of objects drawn as part of the trace of the element.

See also:

parents

Object
Ids of elements on which this element depends directly are stored here.

qdt

JXG.Math.Quadtree

Stores a quad tree if it is required. The quad tree is generated in the curve updates and can be used to speed up the hasPoint method.

quadraticform

Array
Quadratic form representation of circles (and conics)

Default: [[1,0,0],[0,1,0],[0,0,1]]

rendNode

Object
Stores the rendering node for the element.

stdform

Array
[c,b0,b1,a,k,r,q0,q1] See A.E. Middleditch, T.W. Stacey, and S.B. Tor: "Intersection Algorithms for Lines and Circles", ACM Transactions on Graphics, Vol. 8, 1, 1989, pp 25-40. The meaning of the parameters is: Circle: points p=[p0,p1] on the circle fulfill a<p,p> + <b,p> + c = 0 For convenience we also store r: radius k: discriminant = sqrt(<b,b>-4ac) q=[q0,q1] center Points have radius = 0. Lines have radius = infinity. b: normalized vector, representing the direction of the line. Should be put into Coords, when all elements possess Coords.

Default: [1, 0, 0, 0, 1, 1, 0, 0]

subs

Object
Subs contains the subelements, created during the create method.

symbolic

Object
Stores variables for symbolic computations

traces

Object
Keeps track of all objects drawn as part of the trace of the element.

See also:

transformations

Array
Stores the transformations which are applied during update in an array

See also:

type

Number final
Type of the element.

visProp

Object
An associative array containing all visual properties.

Default: empty object

Events

attribute

Notify everytime an attribute is changed.

Event Payload:

  • o Object
    A list of changed attributes and their new value.
  • el Object
    Reference to the element

attribute:<attribute>

This is a generic event handler. It exists for every possible attribute that can be set for any element, e.g. if you want to be notified everytime an element's strokecolor is changed, is the event attribute:strokecolor.

Event Payload:

down

Whenever the user starts to touch or click an element.

Event Payload:

  • e Event
    The browser's event object.

drag

This event is fired whenever the user drags an element.

Event Payload:

  • e Event
    The browser's event object.

mousedown

Whenever the user starts to click an element.

Event Payload:

  • e Event
    The browser's event object.

mousedrag

This event is fired whenever the user drags the element with a mouse.

Event Payload:

  • e Event
    The browser's event object.

mousemove

This event is fired whenever the user is moving the mouse over an element.

Event Payload:

  • e Event
    The browser's event object.

mouseout

This event is fired whenever the user puts the mouse away from an element.

Event Payload:

  • e Event
    The browser's event object.

mouseover

This event is fired whenever the user puts the mouse over an element.

Event Payload:

  • e Event
    The browser's event object.

mouseup

Whenever the user releases the mousebutton over an element.

Event Payload:

  • e Event
    The browser's event object.

move

This event is fired whenever the user is moving over an element.

Event Payload:

  • e Event
    The browser's event object.

out

This event is fired whenever the user is leaving an element.

Event Payload:

  • e Event
    The browser's event object.

over

This event is fired whenever the user is hovering over an element.

Event Payload:

  • e Event
    The browser's event object.

touchdown

Whenever the user starts to touch an element.

Event Payload:

  • e Event
    The browser's event object.

touchdrag

This event is fired whenever the user drags the element on a touch device.

Event Payload:

  • e Event
    The browser's event object.

touchup

Whenever the user stops touching an element.

Event Payload:

  • e Event
    The browser's event object.

up

Whenever the user stops to touch or click an element.

Event Payload:

  • e Event
    The browser's event object.