In categorical track, the genome is separated into a set of intervals and each interval is assigned to a specific category.
Each line of a categorical track file contains four fields:
- chromosome name
- start, 0-based
- category id
The "category id" is a positive integer. The category id references the corresponding category in the "categories" attribute of track definition in datahub. See datahub#categories for details.
Take following steps to submit a categorical track to browser.
1. sort the track file using "sort" command:
sort -k1,1 -k2,2n old_file > new_file
2. compress file
3. index file
tabix -p bed new_file.gz
4. move files "new_file.gz" and "new_file.gz.tbi" to a web server. The two files must be in the same directory. Obtain the URL to "new_file.gz" for submission.