Searches for quantification columns using pattern and header list.
    Calls reader function to do regexp. Returns a single column for
    precursor quant.

def get_quantcols(pattern, oldheader, coltype):
    """Searches for quantification columns using pattern and header list.
    Calls reader function to do regexp. Returns a single column for
    precursor quant."""
    if pattern is None:
       return False
    if coltype == 'precur':
        return reader.get_cols_in_file(pattern, oldheader, single_col=True)