code: def _alphaShapelets(self,shapelets, beta):
          
          output_x = np.zeros((len(shapelets)+1, len(shapelets)+1), 'complex')
          output_y = np.zeros((len(shapelets)+1, len(shapelets)+1), 'complex')
          for nl in range(0,len(shapelets)):
              for nr in range(0,len(shapelets)):
                  a_lr=shapelets[nl][nr]
                  output_x[nl][nr+1]-=a_lr*np.sqrt(nr+1)/2
                  output_y[nl][nr+1]-=a_lr*np.sqrt(nr+1)/2*1j
                  output_x[nl+1][nr]-=a_lr*np.sqrt(nl+1)/2
                  output_y[nl+1][nr]+=a_lr*np.sqrt(nl+1)/2*1j
                  if nl>0:
                      output_x[nl-1][nr]+=a_lr*np.sqrt(nl)/2
                      output_y[nl-1][nr]-=a_lr*np.sqrt(nl)/2*1j
                  if nr>0:
                      output_x[nl][nr-1]+=a_lr*np.sqrt(nr)/2
                      output_y[nl][nr-1]+=a_lr*np.sqrt(nr)/2*1j
          return output_x/beta,output_y/beta
docs: calculates the deflection angles given lensing potential shapelet coefficients (laplacian/2)
          :param shapelets: set of shapelets [l=,r=,a_lr=]
          :type shapelets: array of size (n,3)
          :returns:  set of alpha shapelets.
          :raises: AttributeError, KeyError