Found unexpected keys that do not correspond to any Model output: (param1). Expected: (param1)

Package:

keras

52268

Exception Class:

ValueError

Raise code

                     not any(tf.nest.is_nested(y_p) for y_p in y_pred))

  if (single_output or outputs_are_flat_list) and isinstance(struct, dict):
    output_names = output_names or create_pseudo_output_names(y_pred)
    struct = copy.copy(struct)
    new_struct = [struct.pop(name, None) for name in output_names]
    if struct:
      raise ValueError('Found unexpected keys that do not correspond '
                       'to any Model output: {}. Expected: {}'.format(
                           struct.keys(), output_names))
    if len(new_struct) == 1:
      return new_struct[0]
    return new_struct
  else:
    return struct


def

Links to the raise (1)

https://github.com/keras-team/keras/blob/4a978914d2298db2c79baa4012af5ceff4a4e203/keras/engine/compile_utils.py#L649

Ways to fix

Summary:

This exception can arise when calling the map_to_output_names function. This function takes in 3 parameters: y_pred, output_names, and struct. y_pred is a list of values. output_names is a list of names as strings. struct is a dictionary. The important thing to keep in mind is that the keys of the struct must match the output_names. If they are different from each other you will get this exception. It is important not to reverse the order of the keys and values in the dictionary. The keys must be the output_names, not the values.

Code to Reproduce the Error (Wrong):

from keras.engine.compile_utils import map_to_output_names

y_pred = [1,2,3,4,5]
output_names = ['a', 'b', 'c', 'd', 'e']
struct = {1:'a', 2:'b', 3:'c', 4:'d', 5:'e'}
map_to_output_names(y_pred, output_names, struct)

Error Message:

ValueError                                Traceback (most recent call last)
<ipython-input-68-38522024d135> in <module>()
      4 output_names = ['a', 'b', 'c', 'd', 'e']
      5 struct = {1:'a', 2:'b', 3:'c', 4:'d', 5:'e'}
----> 6 map_to_output_names(y_pred, output_names, struct)

/usr/local/lib/python3.7/dist-packages/keras/engine/compile_utils.py in map_to_output_names(y_pred, output_names, struct)
    649       raise ValueError('Found unexpected keys that do not correspond '
    650                        'to any Model output: {}. Expected: {}'.format(
--> 651                            struct.keys(), output_names))
    652     if len(new_struct) == 1:
    653       return new_struct[0]

ValueError: Found unexpected keys that do not correspond to any Model output: dict_keys([1, 2, 3, 4, 5]). Expected: ['a', 'b', 'c', 'd', 'e']

Working Version (Right):

from keras.engine.compile_utils import map_to_output_names

y_pred = [1,2,3,4,5]
output_names = ['a', 'b', 'c', 'd', 'e']
# keys and values have been swapped
updated_struct = {'a': 1, 'b': 2, 'c': 3, 'd': 4,'e': 5}
map_to_output_names(y_pred, output_names, updated_struct)