train_data是DataFrame类型数据，那么x = training_data[:, :-1]是什么意思

？x = training_data[:, :-1]的意思是取训练数据中除了最后一列之外的所有数据，即取训练数据中的输入部分，用于训练机器学习模型。其中“：”表示取所有行，而“：-1”表示取除了最后一列之外的所有列。

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翻译这段代码:print("start：") start = time.time() K = 9 skf = StratifiedKFold(n_splits=K,shuffle=True,random_state=2018) auc_cv = [] pred_cv = [] for k,(train_in,test_in) in enumerate(skf.split(X,y)): X_train,X_test,y_train,y_test = X[train_in],X[test_in],\ y[train_in],y[test_in] # The data structure 数据结构 lgb_train = lgb.Dataset(X_train, y_train) lgb_eval = lgb.Dataset(X_test, y_test, reference=lgb_train) # Set the parameters 设置参数 params = { 'boosting': 'gbdt', 'objective':'binary', 'verbosity': -1, 'learning_rate': 0.01, 'metric': 'auc', 'num_leaves':17 , 'min_data_in_leaf': 26, 'min_child_weight': 1.12, 'max_depth': 9, "feature_fraction": 0.91, "bagging_fraction": 0.82, "bagging_freq": 2, } print('................Start training..........................') # train gbm = lgb.train(params, lgb_train, num_boost_round=2000, valid_sets=lgb_eval, early_stopping_rounds=100, verbose_eval=100) print('................Start predict .........................') # Predict y_pred = gbm.predict(X_test,num_iteration=gbm.best_iteration) # Evaluate tmp_auc = roc_auc_score(y_test,y_pred) auc_cv.append(tmp_auc) print("valid auc:",tmp_auc) # Test pred = gbm.predict(X, num_iteration = gbm.best_iteration) pred_cv.append(pred) # the mean auc score of StratifiedKFold StratifiedKFold的平均auc分数 print('the cv information:') print(auc_cv) lgb_mean_auc = np.mean(auc_cv) print('cv mean score',lgb_mean_auc) end = time.time() lgb_practice_time=end-start print("......................run with time: {} s".format(lgb_practice_time) ) print("over:*") # turn into array 变为阵列 res = np.array(pred_cv) print("rusult：",res.shape) # mean the result 平均结果 r = res.mean(axis = 0) print('result shape:',r.shape) result = pd.DataFrame() result['company_id'] = range(1,df.shape[0]+1) result['pred_prob'] = r

打印 "start："，并记录开始时间。然后进行 K 折交叉验证，其中 K=9。对于每个交叉验证的训练集和测试集，使用 LightGBM 模型进行训练和预测，并计算每个测试集的 AUC 分数。将每个测试集的预测结果和相应的 AUC 分数存储在数组中。计算 StratifiedKFold 的平均 AUC 分数，并打印出来。将所有测试集的预测结果取平均值作为最终预测结果，并将其存储在 DataFrame 中。最后打印出总运行时间。

ValueError Traceback (most recent call last) Cell In[29], line 91 88 model.summary() 89 #模型训练 ---> 91 history = model.fit( 92 normed_train_data, train_labels, 93 epochs=100, validation_split=0.2, verbose=0) #verbose=表示不输出训练记录 94 #输出训练的各项指标值 95 hist = pd.DataFrame(history.history) File ~\anaconda3\lib\site-packages\keras\utils\traceback_utils.py:70, in filter_traceback.<locals>.error_handler(*args, **kwargs) 67 filtered_tb = _process_traceback_frames(e.__traceback__) 68 # To get the full stack trace, call: 69 # `tf.debugging.disable_traceback_filtering()` ---> 70 raise e.with_traceback(filtered_tb) from None 71 finally: 72 del filtered_tb File ~\AppData\Local\Temp\__autograph_generated_file1dq9vkey.py:15, in outer_factory.<locals>.inner_factory.<locals>.tf__train_function(iterator) 13 try: 14 do_return = True ---> 15 retval_ = ag__.converted_call(ag__.ld(step_function), (ag__.ld(self), ag__.ld(iterator)), None, fscope) 16 except: 17 do_return = False ValueError: in user code: File "C:\Users\lenovo\anaconda3\lib\site-packages\keras\engine\training.py", line 1284, in train_function * return step_function(self, iterator) File "C:\Users\lenovo\anaconda3\lib\site-packages\keras\engine\training.py", line 1268, in step_function ** outputs = model.distribute_strategy.run(run_step, args=(data,)) File "C:\Users\lenovo\anaconda3\lib\site-packages\keras\engine\training.py", line 1249, in run_step ** outputs = model.train_step(data) File "C:\Users\lenovo\anaconda3\lib\site-packages\keras\engine\training.py", line 1050, in train_step y_pred = self(x, training=True) File "C:\Users\lenovo\anaconda3\lib\site-packages\keras\utils\traceback_utils.py", line 70, in error_handler raise e.with_traceback(filtered_tb) from None File "C:\Users\lenovo\anaconda3\lib\site-packages\keras\engine\input_spec.py", line 298, in assert_input_compatibility raise ValueError( ValueError: Input 0 of layer "sequential_21" is incompatible with the layer: expected shape=(None, 14), found shape=(32, 15)

这个错误的原因是您的模型期望的输入形状与实际输入形状不匹配。具体来说，您的模型期望的输入形状是(None, 14)，但您提供给模型的输入形状是(32, 15)。这意味着您的输入数据中有32个样本，每个样本有15个特征，而您的模型期望每个样本只有14个特征。

为了解决这个问题，您需要检查您的输入数据，并确保它们的形状与模型期望的形状匹配。您可以使用NumPy的reshape()函数来改变输入数据的形状，以确保其与模型期望的形状匹配。例如，如果您的输入数据是一个形状为(32, 15)的NumPy数组，您可以使用reshape()函数将其转换为形状为(32, 14)的数组，如下所示：

train_data = train_data.reshape((32, 14))

这样，您就可以将新的train_data输入到您的模型中了，而不会遇到形状不匹配的错误。