function varargout=wqrs(varargin)

 wqrs(recordName,N,N0,signal,threshold,findJ,powerLineFrequency,resample)

    Wrapper to WFDB WQRS:
         http://www.physionet.org/physiotools/wag/wqrs-1.htm

    Creates a WQRS annotation file  at the current MATLAB directory.
    The annotation file will have the same name as the recorName file,
    but followed with the *.wqrs suffix. Use RDANN to read the annoations
    into MATLAB's workspace in order to read the sample QRS locations.

    If recordName is the path to a record at PhysioNet's database, then
    the annation files will be stored in a subdirectory with the same relative 
    path as recordName and under the current directory.


    NOTE: In order to read the generated annotation file using RDANN, it is
    necessary to have the WFDB record (*.hea and *.dat) files in the same 
    directory as the annotation file.


 CITING CREDIT: To credit this function, please cite the following paper in your work:

 Zong, W., G. B. Moody, and D. Jiang."A robust open-source algorithm to detect onset 
 and duration of QRS complexes." Computers in Cardiology, 2003. IEEE, 2003.


 Required Parameters:

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


 Optional Parameters are:

 N 
       A 1x1 integer specifying the sample number at which to stop reading the 
       record file (default read all = N).
 N0 
       A 1x1 integer specifying the sample number at which to start reading the 
       annotion file (default 1 = begining of the record).

 signal
       A 1x1 integer. Specify the signal to obtain the annotation (default
       = 1, first signal).

 threshold
       A 1x1 double. Specify the detection threshold in millivolts
      (default = 100). Use higher values to reduce false detections, or lower values to 
       reduce the number of missed beats. 

 findJ
       A 1x1 boolean. Find and annotate J-points (QRS ends) as well as QRS onsets. 
       Default is false.


 powerLineFrequency
       A 1x1 double. Specify the power line main frequency in Hz (default=
       60 Hz), wqrs will apply a notch filter of the specified frequency 
       to the input signal before length-transforming it. 

 resample
       A 1x1 boolean. Resample the input at 120 Hz if the power line frequency 
       is 60 Hz, or at 150 Hz otherwise (default= false : do not resample).



 Source code written by Wei Zong and George B. Moody. 

 MATLAB wrapper written by Ikaro Silva, 2013
 Last Modified: -
 Version 1.0
 Since 0.0.1

 %Example - Requires write permission to current directory
wqrs('challenge/2013/set-a/a01');