# SimilarityGraph¶

An interactive similarity graph. Given a list of entities that encode a connection strength to the other entities, this component creates a graph with the entities as the nodes, and a link appearing between nodes whose connection strength exceeds some threshold.

The data table contains a list of objects, each with an id field containing a unique identifier for each entity. Each object should also have a numeric fields named by the IDs of the other entities, containing a link strength to each entity. If any entity’s link strength is missing, it is presumed to be 0. Each object may optionally contain a color field, containing a value identifying its color, and a size field, which is either a number (in pixels) for the radius of each node, or a string identifying a field in data that contains a number that will be mapped to the radius for each node. threshold is a numeric value specifying the minimum value for a link strength to appear in the graph. linkDistance sets the desired length of the links in pixels.

This component can be found in the candela/plugins/similaritygraph plugin.

## Example¶

JavaScript

<body>
<script src="//unpkg.com/candela/dist/candela.min.js"></script>
<script>
var el = document.createElement('div')
el.setAttribute('width', 700);
el.setAttribute('width', 700);

document.body.appendChild(el);

var alphabet = 'abcdefghijklmnopqrstuvwxyz';
var vowels = 'aeiou'.split('');

var data = [];
for (var i = 0; i < 26; i++) {
var letter = {
id: alphabet[i],
size: 10 + i,
color: vowels.indexOf(alphabet[i]) > 0 ? 'vowel' : 'consonant'
};

for (var j = 0; j < 26; j++) {
letter[alphabet[j]] = Math.abs(j - i);
}

data.push(letter);
}

var vis = new candela.components.SimilarityGraph(el, {
data: data,
size: 'size',
threshold: 20
});
vis.render();
</script>
</body>


Python

import pycandela

data = [
{'id': 'A', 'class': 0, 'A': 1.0, 'B': 0.5, 'C': 0.3},
{'id': 'B', 'class': 1, 'A': 0.5, 'B': 1.0, 'C': 0.2},
{'id': 'C', 'class': 1, 'A': 0.3, 'B': 0.2, 'C': 1.0}
]

pycandela.components.SimilarityGraph(data=data, id='id', color='class', threshold=0.4)


R

library(candela)

id = c('A', 'B', 'C')
class = c(0, 1, 1)
A = c(1.0, 0.5, 0.3)
B = c(0.5, 1.0, 0.2)
C = c(0.3, 0.2, 1.0)
data = data.frame(id, class, A, B, C)

candela('SimilarityGraph', data=data, id='id', color='class', threshold=0.4)


## Options¶

data (Table)
The data table.
id (String)
The ID field. Can contain any data type, but the value should be unique to each data record.
color (String)
The field used to color the nodes. See Color scales.
size (String or Number)
If a string, the field used to provide the radius for each node; if a number, the radius to use for all nodes.
threshold (Number)
The link strength above which a link will appear in the graph.