def update_select_J(self, blk):
self.update_function(self.param_vals)<EOL>params = np.array(self.param_names)[blk].tolist()<EOL>blk_J = -self.state.gradmodel(params=params, inds=self._inds, flat=False)<EOL>self.J[blk] = blk_J<EOL>self.JTJ = np.dot(self.J, self.J.T)<EOL>if np.any(np.isnan(self.J)) or np.any(np.isnan(self.JTJ)):<EOL><INDENT>raise FloatingPointError('<STR_LIT>')<EOL><DEDENT>
Updates J only for certain parameters, described by the boolean
mask blk.