title: Example for opencv groupRectangle in Python
body: <p>I wanted to ask regarding groupRectangles function.</p>
  
  <p>I am writing the following code in python - </p>
  
  <pre><code>gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)
  #defining the face
  thresh=1
  faces = face_cascade.detectMultiScale(gray, 1.3, 5)
  print faces
  faces_1,weights=cv2.groupRectangles(faces, thresh)
  </code></pre>
  
  <p>where vec is the returning recl from the detectMultiscal step, 1 is the groupThreshold and eps is 0.2</p>
  
  <p>But it is throwing me a runtime error while executing. I tried to run the code by using try-except but still it is throwing me the same error.</p>
  
  <pre><code>Runtime Error!
  
  Program:C:\Python27\pythonw.exe
  
  This application has requested the Runtime to terminate it in an unusual way.
  </code></pre>
  
  <p>It will be of great help if someone can provide some sample grouprectangle code in python, so that i can make my working code in the same format, as in the documentation of this code i am unable to find any examples.</p>
  
  <p>Cheers!</p>