Python 检查模型输入时出错:预期 lstm_1_input 有 3 个维度,但得到的数组具有形状 (339732, 29)

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时间:2020-08-20 00:22:58  来源:igfitidea点击:

Error when checking model input: expected lstm_1_input to have 3 dimensions, but got array with shape (339732, 29)

pythonkeraslstmrecurrent-neural-networkvalueerror

提问by Saurav--

My input is simply a csv file with 339732 rows and two columns :

我的输入只是一个包含 339732 行和两列的 csv 文件:

  • the first being 29 feature values, i.e. X
  • the second being a binary label value, i.e. Y
  • 第一个是 29 个特征值,即 X
  • 第二个是二进制标签值,即 Y

I am trying to train my data on a stacked LSTM model:

我正在尝试在堆叠的 LSTM 模型上训练我的数据:

data_dim = 29
timesteps = 8
num_classes = 2

model = Sequential()
model.add(LSTM(30, return_sequences=True,
               input_shape=(timesteps, data_dim)))  # returns a sequence of vectors of dimension 30
model.add(LSTM(30, return_sequences=True))  # returns a sequence of vectors of dimension 30
model.add(LSTM(30))  # return a single vector of dimension 30
model.add(Dense(1, activation='softmax'))

model.compile(loss='binary_crossentropy',
              optimizer='rmsprop',
              metrics=['accuracy'])

model.summary()
model.fit(X_train, y_train, batch_size = 400, epochs = 20, verbose = 1)

This throws the error:

这会引发错误:

Traceback (most recent call last): File "first_approach.py", line 80, in model.fit(X_train, y_train, batch_size = 400, epochs = 20, verbose = 1)

ValueError: Error when checking model input: expected lstm_1_input to have 3 dimensions, but got array with shape (339732, 29)

回溯(最近一次调用):文件“first_approach.py​​”,第 80 行,在 model.fit(X_train, y_train, batch_size = 400, epochs = 20,verbose = 1)

ValueError:检查模型输入时出错:预期 lstm_1_input 有 3 个维度,但得到了具有形状的数组 (339732, 29)

I tried reshaping my input using X_train.reshape((1,339732, 29))but it did not work showing error:

我尝试使用重塑我的输入,X_train.reshape((1,339732, 29))但它没有工作显示错误:

ValueError: Error when checking model input: expected lstm_1_input to have shape (None, 8, 29) but got array with shape (1, 339732, 29)

ValueError:检查模型输入时出错:预期 lstm_1_input 具有形状 (None, 8, 29) 但得到形状为 (1, 339732, 29) 的数组

How can I feed in my input to the LSTM ?

如何将我的输入输入到 LSTM 中?

回答by Saurav--

Setting timesteps = 1(since, I want one timestep for each instance) and reshaping the X_train and X_test as:

设置timesteps = 1(因为我希望每个实例都有一个时间步长)并将 X_train 和 X_test 重塑为:

import numpy as np
X_train = np.reshape(X_train, (X_train.shape[0], 1, X_train.shape[1]))
X_test = np.reshape(X_test, (X_test.shape[0], 1, X_test.shape[1]))

This worked!

这有效!

回答by shadi

For timesteps != 1, you can use the below function (adapted from here)

对于timesteps != 1,您可以使用以下功能(改编自此处

import numpy as np
def create_dataset(dataset, look_back=1):
  dataX, dataY = [], []
  for i in range(len(dataset)-look_back+1):
    a = dataset[i:(i+look_back), :]
    dataX.append(a)
    dataY.append(dataset[i + look_back - 1, :])
  return np.array(dataX), np.array(dataY)

Examples

例子

X = np.reshape(range(30),(3,10)).transpose()
array([[ 0, 10, 20],
       [ 1, 11, 21],
       [ 2, 12, 22],
       [ 3, 13, 23],
       [ 4, 14, 24],
       [ 5, 15, 25],
       [ 6, 16, 26],
       [ 7, 17, 27],
       [ 8, 18, 28],
       [ 9, 19, 29]])

create_dataset(X, look_back=1 )
(array([[[ 0, 10, 20]],
       [[ 1, 11, 21]],
       [[ 2, 12, 22]],
       [[ 3, 13, 23]],
       [[ 4, 14, 24]],
       [[ 5, 15, 25]],
       [[ 6, 16, 26]],
       [[ 7, 17, 27]],
       [[ 8, 18, 28]],
       [[ 9, 19, 29]]]),
array([[ 0, 10, 20],
       [ 1, 11, 21],
       [ 2, 12, 22],
       [ 3, 13, 23],
       [ 4, 14, 24],
       [ 5, 15, 25],
       [ 6, 16, 26],
       [ 7, 17, 27],
       [ 8, 18, 28],
       [ 9, 19, 29]]))

create_dataset(X, look_back=3)
(array([[[ 0, 10, 20],
        [ 1, 11, 21],
        [ 2, 12, 22]],
       [[ 1, 11, 21],
        [ 2, 12, 22],
        [ 3, 13, 23]],
       [[ 2, 12, 22],
        [ 3, 13, 23],
        [ 4, 14, 24]],
       [[ 3, 13, 23],
        [ 4, 14, 24],
        [ 5, 15, 25]],
       [[ 4, 14, 24],
        [ 5, 15, 25],
        [ 6, 16, 26]],
       [[ 5, 15, 25],
        [ 6, 16, 26],
        [ 7, 17, 27]],
       [[ 6, 16, 26],
        [ 7, 17, 27],
        [ 8, 18, 28]],
       [[ 7, 17, 27],
        [ 8, 18, 28],
        [ 9, 19, 29]]]),
array([[ 2, 12, 22],
       [ 3, 13, 23],
       [ 4, 14, 24],
       [ 5, 15, 25],
       [ 6, 16, 26],
       [ 7, 17, 27],
       [ 8, 18, 28],
       [ 9, 19, 29]]))

回答by Ashok Kumar Jayaraman

Reshape input for LSTM:

重塑 LSTM 的输入:

X = array([[10, 20, 30], [40, 50, 60], [70, 80, 90]])
X_train = X.reshape(1, 3, 3) # X.reshape(samples, timesteps, features)