To create a bigBed track, follow these steps (for concrete Unix commands, see the examples below on this page):
Step 1. Create a BED format file following the directions here. When converting a BED file to a bigBed file, you are limited to one track of data in your input file; therefore, you must create a separate BED -file for each data track. Your BED file must be sorted. +file for each data track.
If your BED file was originally a custom track, remove any existing
"track" or "browser" lines from your BED file so that it
-contains only data. Also the input BED must be sorted, performed with this command:
-sort -k1,1 -k2,2n unsorted.bed > input.bed
+contains only data.
+
+Your file does not need to be sorted by chromosome name, but all entries for a
+single chromosome must be together and sorted by chromosome start position. If you're not
+sure if this is true for your BED file, it may be easiest to sort the file
+using the "-sort" option for bedToBigBed.
+Finally, if your BED files are large, they can be compressed using gzip (e.g. myTrack.bed.gz) and still read
+by bedToBigBed.
Step 2.
Download the bedToBigBed program from the
binary utilities directory.
Example #2 below shows the exact Unix command.
The bedToBigBed program can be run with several additional options. Some of these,
such as the -as and -type options, are used in examples below. The
-type option, describes the size of the bigBed file, -type=bedN[+[P]],
where N is an integer between 3 and 12 and the optional +[P] parameter
specifies the number of extra fields, not required, but preferred. Describing the size of the bigBed file