crossings

Description

A crossings element encodes the number and signs of all individual crossings in a knot/link diagram.

The total number of crossings must be specified by the size attribute. The individual crossings are numbered 0, 1, 2, and so on.

The character data of this XML element should be a whitespace-separated list of signs, each + or -. There should be size signs in total, representing the signs of crossings 0, 1, 2, ... in order.

Attributes

Example

The following XML snippet represents the Whitehead link.

<crossings size="5">
- - + + -
</crossings>
<connections>
_1 ^1
_2 ^4
_4 ^3
_0 ^2
_3 ^0
</connections>
<components size="2">
^0 _0
</components>