$chrom='chr1'; 
$start=9839;
$stop=9841;

##</code><code>##

_DATA_
variableStep chrom=chr1
9837	0.010
9838	0.008
9839	0.007
9840	0.004
9841	0.002
9842	0.001
variableStep chrom=chr2
9837	0.090
9838	0.038
9839	0.017
9840	0.044
9841	0.052
9842	0.091