AttributeError: 'NoneType' 对象没有属性 'name'（与不同的 tensorflow 版本有关）

Question

While running the jupyter notebook online in google colab, no error is coming out, but while running the code in offline mode, it's giving following error. :

---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)
<ipython-input-30-04f071b889cd> in <module>
      4     start_time = time.time()
      5     x, min_val, info = fmin_l_bfgs_b(evaluator.loss, x.flatten(),
----> 6                            fprime=evaluator.grads, maxfun=20)
      7     print(min_val)
      8     end_time = time.time()

~/anaconda3/lib/python3.7/site-packages/scipy/optimize/lbfgsb.py in fmin_l_bfgs_b(func, x0, fprime, args, approx_grad, bounds, m, factr, pgtol, epsilon, iprint, maxfun, maxiter, disp, callback, maxls)
    197 
    198     res = _minimize_lbfgsb(fun, x0, args=args, jac=jac, bounds=bounds,
--> 199                            **opts)
    200     d = {'grad': res['jac'],
    201          'task': res['message'],

~/anaconda3/lib/python3.7/site-packages/scipy/optimize/lbfgsb.py in _minimize_lbfgsb(fun, x0, args, jac, bounds, disp, maxcor, ftol, gtol, eps, maxfun, maxiter, iprint, callback, maxls, **unknown_options)
    333             # until the completion of the current minimization iteration.
    334             # Overwrite f and g:
--> 335             f, g = func_and_grad(x)
    336         elif task_str.startswith(b'NEW_X'):
    337             # new iteration

~/anaconda3/lib/python3.7/site-packages/scipy/optimize/lbfgsb.py in func_and_grad(x)
    283     else:
    284         def func_and_grad(x):
--> 285             f = fun(x, *args)
    286             g = jac(x, *args)
    287             return f, g

~/anaconda3/lib/python3.7/site-packages/scipy/optimize/optimize.py in function_wrapper(*wrapper_args)
    324     def function_wrapper(*wrapper_args):
    325         ncalls[0] += 1
--> 326         return function(*(wrapper_args + args))
    327 
    328     return ncalls, function_wrapper

<ipython-input-27-551cb8cb7b3f> in loss(self, x)
      6     def loss(self, x):
      7         assert self.loss_value is None
----> 8         loss_value, grad_values = eval_loss_and_grads(x)
      9         self.loss_value = loss_value
     10         self.grad_values = grad_values

<ipython-input-26-8de948cd1256> in eval_loss_and_grads(x)
      1 def eval_loss_and_grads(x):
      2     x = x.reshape((1, height, width, 3))
----> 3     outs = f_outputs([x])
      4     loss_value = outs[0]
      5     grad_values = outs[1].flatten().astype('float64')

~/anaconda3/lib/python3.7/site-packages/tensorflow/python/keras/backend.py in __call__(self, inputs)
   3287         feed_symbols != self._feed_symbols or self.fetches != self._fetches or
   3288         session != self._session):
-> 3289       self._make_callable(feed_arrays, feed_symbols, symbol_vals, session)
   3290 
   3291     fetched = self._callable_fn(*array_vals,

~/anaconda3/lib/python3.7/site-packages/tensorflow/python/keras/backend.py in _make_callable(self, feed_arrays, feed_symbols, symbol_vals, session)
   3213     # Handle fetches.
   3214     for x in self.outputs + self.fetches:
-> 3215       callable_opts.fetch.append(x.name)
   3216     # Handle updates.
   3217     callable_opts.target.append(self.updates_op.name)

AttributeError: 'NoneType' object has no attribute 'name'

In offline mode, following versions of tensoflow and keras respectively : 1.14.0, 2.3.0

In google colab, following versions of tensoflow and keras respectively : 1.15.0, 2.2.5

[ Note : i checked the code, and when i ran it on colab, it was working. ]

The code is :

import time
for i in range(iterations):
    print('Start of iteration', i)
    start_time = time.time()
    x, min_val, info = fmin_l_bfgs_b(evaluator.loss, x.flatten(),
                           fprime=evaluator.grads, maxfun=20)
    print(min_val)
    end_time = time.time()
    print('Iteration %d completed in %ds' % (i, end_time - start_time))

Answer 1

尝试再次安装软件包，因为它解决了我的问题，就像我在 anaconda 环境中再次重新安装了一些冲突的软件包一样