getChromBounds

def getChromBounds(data):
    """
    getChromBounds
    """
    chrom= data.geno['col_header']['chrom'][:]
    posCum = getCumPos(data)
    n_chroms = int(chrom.max())
    chrom_bounds = []
    for chrom_i in range(2,n_chroms+1):
        I1 = chrom==chrom_i
        I0 = chrom==chrom_i-1
        _cb = 0.5*(posCum[I0].max()+posCum[I1].min())
        chrom_bounds.append(_cb)
    return chrom_bounds