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rdann

    function varargout=rdann(varargin)

     [ann,anntype,subtype,chan,num,comments]=rdann(recordName, annotator, C, N, N0, AT)

        Wrapper to WFDB RDANN:
             http://www.physionet.org/physiotools/wag/rdann-1.htm

     NOTE: The WFDB Toolbox uses 0 based index, and MATLAB uses 1 based index.
           Due to this difference annotation values ('ann') are shifted inside
           this function in order to be compatible with the WFDB native
           library. The MATLAB user should leave the indexing conversion to
           the WFDB Toolbox.

     Reads a WFDB annotation and returns:

     ann
           Nx1 integer vector of the annotation locations in samples
           with respect to the beginning of the record.
           To convert this vector to a string of time stamps see WFDBTIME.

     anntype
           Nx1 character vector describing the annotation types.
           For a list of standard annotation codes used by PhyioNet, see:
                 http://www.physionet.org/physiobank/annotations.shtml

     subtype
           Nx1 integer vector describing annotation subtype.

     chan
           Nx1 integer vector describing annotation channel.

     num
           Nx1 integer vector describing annotation NUM.

     comments
           Nx1 cell of strings describing annotation comments.

     Required Parameters:

     recorName
           String specifying the name of the record in the WFDB path or
           in the current directory.

     annotator
           String specifying the name of the annotation file in the WFDB path or
           in the current directory.

     Optional Parameters are:

     C
           An integer scalar. Return only the annotations with chan = C.
     N
           An integer specifying the sample number at which to stop reading the
           record file. Default read all.
     N0
           A 1x1 integer specifying the sample number at which to start reading the
           annotion file. Default = 1, begining of the record.

     AT
           The anntype character. Return only annotations with subtype = S.
           Default is empty, which returns all annotations.

     **OPTIMIZATION NOTE: This function has been optimized for cases in which
     only the annotation sample vector is required, ie for function calls of
     the type:

      ann=rdann(recordName, annotator, C, N, N0, AT);

      For these cases, no string parsing is required and the formatting is
      done at the Java level, increasing substantially the processing speed.

     Written by Ikaro Silva, 2013
     Last Modified: January 4, 2017
     Version 2.1
     Since 0.0.1

     %Example 1- Read a signal and annotation from PhysioNet's Remote server:
    [signal,Fs,tm]=rdsamp('challenge/2013/set-a/a01');
    [ann]=rdann('challenge/2013/set-a/a01','fqrs');
    plot(tm,signal(:,1));hold on;grid on
    plot(tm(ann),signal(ann,1),'ro','MarkerSize',4)

    %Example 2- Read annotation from the first 500 samples only
     ann=rdann('mitdb/100','atr',[],500);

    %Example 3- Read annotations with anntype = 'V' only.
     annV=rdann('mitdb/100', 'atr', [],[],[],'V');

     See also wfdbtime, wrann