Track list and Facet Table
The facet table creates an ordered table under the Tracks button.
To begin, create the track list using the following example as a guide:
[
{
"type": "bedj",
"file": "path/to/file.gz",
"name": "my track"
},
{ … another track … },
{
"isfacet": true,
… a facet table, see below …
}
]
A facet table can be encoded in the JSON file as an object.
{
"isfacet": true,
"name": "My facet table",
"tracks": [
{
"type": "bigwig",
"assay": "WGBS",
"sample": "Retina Wk 10",
"file": "retina/hg19/wgbs/Methyl-FW10.bw",
"name": "Retina Wk 10, WGBS"
},
{
"type": "bigwig",
"assay": "WGBS",
"sample": "Retina Wk 14",
"file": "retina/hg19/wgbs/Methyl-FW14.bw",
"name": "Retina Wk 14, WGBS"
},
… more tracks
]
}
In which “assay” and “sample” attributes are required for all tracks in a table. Then, unique lists of assay and sample names from the track list are used to build a facet table accessible from the Track button. Click on a cell, sample label, or assay header to selectively show/hide tracks.
Samples may be presented in a two or three level hierarchical structure, shown on the left-hand side of the facet table.
To create a two level structure, add the “level1” attribute.
{
"assay": "WGBS",
"type": "bigwig",
"name": "WGBS RB patient rep1",
"level1": "RB",
"sample": "patient rep1",
"file": "retina/hg19/wgbs/Methyl-RB-D1.bw"
},
… more tracks
This creates a new column on the farthest left hand side grouping samples assigned to the same value. A clickable link is also created, so all tracks in the group may be shown or hidden at once.
To create a two level structure, add the “level1” and “level2” attributes.
{
"assay": "WGBS",
"type": "bigwig",
"name": "WGBS RB patient rep1",
"level1": "RB",
"level2": "patient",
"sample": "patient rep1",
"file": "retina/hg19/wgbs/Methyl-RB-D1.bw"
},
… more tracks
“level1” still appears on the farthest left column and “level2” creates a new column in the middle. Both attributes create clickable links to show or hide all tracks in the specified level, at once.
