def _common(s1, s2, i1, i2):
c = len(set(s1).intersection(s2))<EOL>t = min(len(s1), len(s2))<EOL>pct = <NUM_LIT:1.0> * c / t * t<EOL>is_gt = up_threshold(pct, t * <NUM_LIT:1.0>, parameters.similar)<EOL>logger.debug("<STR_LIT>" % (<NUM_LIT:1.0> * c / t, i1, i2, is_gt))<EOL>if pct < parameters.similar and is_gt and pct > <NUM_LIT:0>:<EOL><INDENT>pct = parameters.similar<EOL><DEDENT>return pct / t<EOL>
calculate the common % percentage of sequences