我正在尝试运行cnn代码，即“深度学习协调波束成形”。

如下所示，有一个"UnboundLocalError: local variable 'batch_index' referenced before assignment"。我不在代码中使用变量'batch_index'。我该如何处理该错误？

我使用Windows OS，Python 3.6.8，Keras 2.3.1和Tensorflow 2.0.0。 我搜寻网，但不知道该如何处理。

from __future__ import division
import os,keras 
os.environ["KERAS_BACKEND"] = "theano"
os.environ["THEANO_flaGS"]  = "device=gpu%d"%(1)
import numpy as np
import theano as th
import theano.tensor as T
from keras.utils import np_utils
import keras.models as models
from keras.layers.core import Reshape,Dense,Dropout,activation
from keras.optimizers import adam
from scipy.io import loadmat,savemat
import os.path
from keras import backend as K    


# Model training function
def train(In_train,Out_train,In_test,Out_test,nb_epoch,batch_size,dr,num_hidden_layers,nodes_per_layer,loss_fn,n_BS,n_beams):

    in_shp = list(In_train.shape[1:])

    AP_models = []

    for idx in range(0,n_BS*n_beams-2,n_beams):
        idx_str = str(idx / n_beams + 1)

        model = models.Sequential()
        model.add(Dense(nodes_per_layer,activation='relu',init='he_normal',name="dense" + idx_str + "1",input_shape=in_shp))
        model.add(Dropout(dr))
        for h in range(num_hidden_layers):
            model.add(Dense(nodes_per_layer,name="dense" + idx_str + "h" + str(h)))
            model.add(Dropout(dr))

        model.add(Dense(n_beams,name="dense" + idx_str + "o"))
        model.compile(loss=loss_fn,optimizer='adam')
        model.summary()
        # perform training ...
        earlyStoppingCallback = \
            keras.callbacks.EarlyStopping(monitor='val_loss',patience=5,verbose=0,mode='auto')
        filepath = 'DLCB_code_output/Results_mmWave_ML'+str(idx)
        history = model.fit(In_train,Out_train[:,idx:idx + n_beams],batch_size=batch_size,nb_epoch=nb_epoch,verbose=2,validation_data=(In_test,Out_test[:,idx:idx + n_beams]),callbacks = [
                                keras.callbacks.ModelCheckpoint(filepath,monitor='val_loss',save_best_only=True,mode='auto'),keras.callbacks.EarlyStopping(monitor='val_loss',mode='auto')
                            ])

        # we re-load the best weights once training is finished
        model.load_weights(filepath)

        AP_models.append(model)


    return AP_models

# Reading input and output sets generated from MATLAB
In_set_file=loadmat('DLCB_dataset/DLCB_input.mat')
Out_set_file=loadmat('DLCB_dataset/DLCB_output.mat')

In_set=In_set_file['DL_input']
Out_set=Out_set_file['DL_output']

# Parameter initialization
num_user_tot=In_set.shape[0]
n_DL_size=[.001,.05,.1,.15,.2,.25,.3,.35,.4,.45,.5,.55,.6,.65,.7,.75,.8]
count=0
num_tot_TX=4
num_beams=128


for DL_size_ratio in n_DL_size:

    print (DL_size_ratio)
    count=count+1
    DL_size=int(num_user_tot*DL_size_ratio)

    np.random.seed(2016)
    n_examples = DL_size
    num_train  = int(DL_size * 0.8)
    num_test   = int(num_user_tot*.2)

    train_index = np.random.choice(range(0,num_user_tot),size=num_train,replace=False)
    rem_index = set(range(0,num_user_tot))-set(train_index)
    test_index= list(set(np.random.choice(list(rem_index),size=num_test,replace=False)))

    In_train = In_set[train_index]
    In_test =  In_set[test_index] 

    Out_train = Out_set[train_index]
    Out_test = Out_set[test_index]


    # Learning model parameters
    nb_epoch = 10     
    batch_size = 100  
    dr = 0.05                  # dropout rate  
    num_hidden_layers=4
    nodes_per_layer=In_train.shape[1]
    loss_fn='mean_squared_error'

    # Model training
    AP_models = train(In_train,num_tot_TX,num_beams)


    # Model running/testing
    DL_Result={}
    for id in range(0,1): 
        beams_predicted=AP_models[id].predict( In_test,batch_size=10,verbose=0)

        DL_Result['TX'+str(id+1)+'Pred_Beams']=beams_predicted
        DL_Result['TX'+str(id+1)+'Opt_Beams']=Out_test[:,id*num_beams:(id+1)*num_beams]

    DL_Result['user_index']=test_index
    savemat('DLCB_code_output/DL_Result'+str(count),DL_Result)