sequence selection options
--------------------------

.. cmdoption::  -s <REGULAR_PATTERN>, --sequence=<REGULAR_PATTERN>

                        regular expression pattern used to select the
                        sequence. The pattern is case insensitive
                        
.. cmdoption::  -D <REGULAR_PATTERN>, --definition=<REGULAR_PATTERN>

                        regular expression pattern matched against the
                        definition of the sequence. The pattern is case
                        sensitive
                        
.. cmdoption::  -I <REGULAR_PATTERN>, --identifier=<REGULAR_PATTERN>

                        regular expression pattern matched against the
                        identifier of the sequence. The pattern is case
                        sensitive
                        
.. cmdoption::  --id-list=<FILENAME>

                        a file containing a list of sequence identifiers to
                        be selected.
                        
.. cmdoption::  -a <ATTRIBUTE_NAME>:<REGULAR_PATTERN>, --attribute=<ATTRIBUTE_NAME>:<REGULAR_PATTERN>

                        regular expression pattern matched against the
                        attributes of the sequence. the value of this atribute
                        is of the form : attribute_name:regular_pattern. The
                        pattern is case sensitive.Several -a option can be
                        used on the same commande line.
                        
.. cmdoption::  -A <ATTRIBUTE_NAME>, --has-attribute=<ATTRIBUTE_NAME>

                        select sequence with attribute <ATTRIBUTE_NAME>
                        defined
                        
.. cmdoption::  -p <PYTHON_EXPRESSION>, --predicat=<PYTHON_EXPRESSION>

                        python boolean expression to be evaluated in the
                        sequence context. The attribute name can be used in
                        the expression as variable name .An extra variable
                        named 'sequence' refersto the sequence object itself.
                        Several -p option can be used on the same commande
                        line.
                        
.. cmdoption::  -L <##>, --lmax=<##>  

                        keep sequences shorter than lmax
                        
.. cmdoption::  -l <##>, --lmin=<##>  

                        keep sequences longer than lmin
                        
