function varargout=physionetdb(varargin)

 db_list=physionetdb(db_name,DoBatchDownload,webBrowserFlag)


 Lists all the available databases at PhysioNet
 (http://physionet.org/physiobank/) or list all available records in a database.
 Users can read the signals (waveforms) or annotations (labels) using the WFDB
 App Toolbox's functions such as RDSAMP. Options are

 Optional Input Parameters:
 db_name
          String specifying the datbase to query for available records.
          If left empty (default) a list of available database names is
          returned. NOTE: Some databases (such as 'mimic2db') have a huge
          number of records so that querying the records in the database
          can take a long time.

 DoBatchDownload
          If 'db_name' is present, setting this flag to true
          (DoBatchDownload=1), will download all records of the database
          db_name to a subdirectory in the current directory called
          'db_name'. Default is false. Note: requires that the user have
          write permission to the current directory.

          NOTE: This function currently does not perform any checksum in order
          to verify that the files were dwnloaded properly.

 webBrowserFlag
          Boolean. If true, displays database information in MATLAB's
          web browser (default = 0).

 Output Parameters
 db_list -(Optional) Cell array list of elements. If an output
          is not provided, results are displayed to the screen.
          The returned valued are either a list of database names to query
          (if db_name is empty), or a list of available records that can
          be read via RDSAMP (if db_name is a name of a valid database as
          given by the return list when db_name is empty).

 Author: Ikaro Silva, 2013
 Since: 0.0.1
 Last Modified: April 8, 2015


 %Example 1 - List all available databases from PhysioNet into the screen
 physionetdb

 %Example 2 - List all available databases from PhysioNet in web browser
 physionetdb([],[],1)

 %Example 3- List all available records in the ucddb database.
 db_list=physionetdb('ucddb')

 %Example 4- Download all records for database MITDB
  physionetdb('mitdb',1);

 %Example 5- List all records for database MITDB on a web browser
 physionetdb('mitdb',[],1);