Correct LSTM model to predict shuffled data

Question

For a year I've been collecting data from my RPi:

[0 core load, 1 core load, 2 core load, 3 core load, environment temperature, fan speed, CPU temperature]

Now I want to build a model with Keras and LSTMs to make a prediction of core temperature based on a vector [0 core load, 1 core load, 2 core load, 3 core load, environment temperature, fan speed].

The main problem is that I can not compose this data into time series, because I've sorted it by 0 core load unintentionally. So this data can be considered as shuffled.

Current model does not work at all:

model = Sequential()

model.add(Dense(128, activation='relu'))
model.add(Dense(128, activation='relu'))
model.add(Dense(128, activation='relu'))
model.add(Dense(128, activation='relu'))
model.add(LSTM(128))
model.add(LSTM(128))

model.add(Dense(1, activation='sigmoid'))

Training summary:

Epoch 1/128
6483/6483 [==============================] - 45s 7ms/step - loss: 140033.1094 - val_loss: 119426.7812
Epoch 2/128
6483/6483 [==============================] - 45s 7ms/step - loss: 140032.5156 - val_loss: 119426.7812
Epoch 3/128
6483/6483 [==============================] - 45s 7ms/step - loss: 140034.2500 - val_loss: 119426.7812
Epoch 4/128
6483/6483 [==============================] - 45s 7ms/step - loss: 140040.8438 - val_loss: 119426.7812
Epoch 5/128
5071/6483 [======================>.......] - ETA: 9s - loss: 140302.2812

How can I predict such shuffled data with LSTM? I'm currently stuck.

Answer 1

The input for an RNN like LSTM should be in the shape of (batch, timestep, features).

Base on my experience, if your current X_train.shape is in 2D you would like to reshape it into 3D array by X_train = np.reshape(X_train, (X_train.shape[0], X_train.shape[1], 1)) Then It will be something like (total number of samples, 7,1); 7 is because you have 7 different features.

By the way, you probably would like to start with a single layer of Dense and LSTM.

Further, using multiple layers of LSTM would require you to set return_sequences to True for all LSTM layers before the last one

model.add(LSTM(128,return_sequences = True))
model.add(LSTM(128))