help with bowtie-inspect

[nimmi]

Hi,

In order to convert the bedgraph file to bigwig file format I need chrom.sizes file. I downloaded pre-built index files from Tophat website to run Tophat. I tried to use bowtie-inspect with -n option on these pre-built index files to create chrom.sizes file, but it generates only chromosome names and not the size of chromosome. Could someone please let me know what other options should I use or if there are any other alternatives to generate this file using pre-built indexes?

Thanks in advance for your responses,
Nirmala