docs: def ComputeAntennaResponse(theta, phi, psi, detRespTensor):
      """ ComputeAntennaResponse - function to compute F+,x of a detector
  	characterised by detRespTensor to a source located at (theta,phi,psi) 
  	in geocentric coordinates.
  
  	theta - Polar angle of source's sky position in geocentric
                  coordinates.
  	phi -  Azimuthal angle of source's sky position in geocentric
                 coordinates.
   	psi - Polarisation angle of gravitational waves, measured
  	      counter-clockwise about direction of propagation from line of 
  	      constant theta pointing to decreasing phi to positive x-axis of 
  	      source coordinates.
          detRespTensor - (3,3) array containing detector response tensor.
  
  	Returns Fp - Antenna response of detectorName to the plus GW
  		polarisation of a source at (RA,Dec,psi).
  		Fc - Antenna response of detectorName to the cross GW
  		polarisation of a source at (RA,Dec,psi).
  
          Sarah Gossan 2012. Last updated 02/18/14. """
  
      # Define axes of wave frame in terms of axes of Earth-centered axes and
      # source angles
      X = np.zeros(3)
      Y = np.zeros(3)
      X[0] = np.sin(phi)*np.cos(psi) - np.sin(psi)*np.cos(phi)*np.cos(theta)
      X[1] = -np.cos(phi)*np.cos(psi) - np.sin(psi)*np.sin(phi)*np.cos(theta)
      X[2] = np.sin(psi)*np.sin(theta)
      Y[0] = -np.sin(phi)*np.sin(psi) - np.cos(psi)*np.cos(phi)*np.cos(theta)
      Y[1] = np.cos(phi)*np.sin(psi) - np.cos(psi)*np.sin(phi)*np.cos(theta)
      Y[2] = np.sin(theta)*np.cos(psi)
      
      # Construct polarisation vectors e+,x as
      # e+ = (X \outerprod X - Y \outerprod Y)
      # ex = (X \outerprod Y + Y \outerprod X)
      ep = np.zeros((3,3),float)
      ec = np.zeros((3,3),float)
      
      for i in range(0,3):
          for j in range(0,3):
  	    ep[i,j] = X[i]*X[j] - Y[i]*Y[j]
  	    ec[i,j] = X[i]*Y[j] + Y[i]*X[j]
  
      # Construct Fp,Fc as 
      # Fp = \sum_ij(D_ij ep_ij) 
      # Fc = \sum_ij(D_ij ec_ij)
      Fp = 0.
      Fc = 0.
      for i in range(0,3):
  	for j in range(0,3):
  	    Fp += detRespTensor[i,j]*ep[i,j]
   	    Fc += detRespTensor[i,j]*ec[i,j]
  
      return Fp,Fc