code: def fill_jacobian_column(self, jaccol, coordinates):
          
          q, g = self.icfn(coordinates[list(self.indexes)], 1)
          for i, j in enumerate(self.indexes):
              jaccol[3*j:3*j+3] += g[i]
          return jaccol
docs: Fill in a column of the Jacobian.
  
             Arguments:
              | ``jaccol`` -- The column of Jacobian to which the result must be
                              added.
              | ``coordinates`` -- A numpy array with Cartesian coordinates,
                                   shape=(N,3)