Parallel

Element

A parallel is a line through a given point, parallel to a given line.

If original line is given as a JSXGraph line object, the resulting parallel line will be defined by the given point and an infinitely far away point (an ideal point). That means, the line can not be shortened to a segment.

If the original line is given as two points, the resulting parallel line can be shortened to a a segment.

Usage (signatures)
board.create('parallel', [l, p]);

The constructed line contains p and has the same slope as l. The order of the parameters is irrelevant.

Parameters
Name Type Description
l Line
p PointLike
Example

Create parallel to l1 through point p3

var p1 = board.create('point', [0.0, 2.0]);
var p2 = board.create('point', [2.0, 1.0]);
var l1 = board.create('line', [p1, p2]);

var p3 = board.create('point', [3.0, 3.0]);
var pl1 = board.create('parallel', [l1, p3]);
board.create('parallel', [p1, p2, p]);

Alternative parameters are [p1, p2, p]: The constructed line contains p and has the same slope as the line through p1 and p2.

Parameters
Name Type Description
p1 PointLike
p2 PointLike
p PointLike
Example

Create segment, parallel to line [p1, p2] through point p3

var p1, p2, p3, l1, pl1;

p1 = board.create('point', [0.0, 2.0]);
p2 = board.create('point', [2.0, 1.0]);
l1 = board.create('line', [p1, p2]);

p3 = board.create('point', [1.0, 3.0]);
pl1 = board.create('parallel', [p1, p2, p3], {straightFirst: false, straightLast: false});
Attributes

Own

point

point

Description

Attributes of helper point of normal.

Type
Point
Source
options.js, line 7948

Inherited

none

Members

Own

point

point : JXG.Point

Description

Helper point used to create the parallel line. This point lies on the line at infinity, hence it's not visible, not even with visible set to true. Creating another line through this point would make that other line parallel to the create parallel.

Type
JXG.Point
Source
element/composition.js, line 1105

Inherited

none

Throws

If the element cannot be constructed with the given parent objects an exception is thrown.

Type
Error

Details

Type
JXG.Line
Source
element/composition.js, line 956