Guess logfile path produced by Mothur

        This method checks the working directory for log files
        generated by Mothur.  It will raise an ApplicationError if no
        log file can be found.

        Mothur generates log files named in a nondeterministic way,
        using the current time.  We return the log file with the most
        recent time, although this may lead to incorrect log file
        detection if you are running many instances of mothur
        simultaneously.

def _derive_log_path(self):
        """Guess logfile path produced by Mothur

        This method checks the working directory for log files
        generated by Mothur.  It will raise an ApplicationError if no
        log file can be found.

        Mothur generates log files named in a nondeterministic way,
        using the current time.  We return the log file with the most
        recent time, although this may lead to incorrect log file
        detection if you are running many instances of mothur
        simultaneously.
        """
        filenames = listdir(self.WorkingDir)
        lognames = [
            x for x in filenames if re.match(
                "^mothur\.\d+\.logfile$",
                x)]
        if not lognames:
            raise ApplicationError(
                'No log file detected in directory %s. Contents: \n\t%s' % (
                    input_dir, '\n\t'.join(possible_logfiles)))
        most_recent_logname = sorted(lognames, reverse=True)[0]
        return path.join(self.WorkingDir, most_recent_logname)