I try to this exercise of tensorflow, when I give xs
and ys
higher value during training, the loss starts increasing. Why this happens? Am I doing something wrong?
It looks OK when max
is 19
but not for 20
.
import tensorflow as tf
import numpy as np
from tensorflow import keras
def main():
print(tf.__version__)
model = tf.keras.Sequential([keras.layers.Dense(units=1, input_shape=[1])])
model.compile(optimizer='sgd', loss="mean_squared_error")
min = 0
max = 20 # the loss will increse if gives more data
xs = np.array([float(x) for x in range(min, max)], dtype=np.float32)
ys = np.array([float(3 * x 1) for x in range(min, max)], dtype=np.float32)
print(xs, sep=',')
print(ys, sep=',')
model.fit(xs, ys, epochs=10)
print(model.predict([100]))
if __name__ == "__main__":
main()
Results:
Epoch 1/10
1/1 [==============================] - 0s 85ms/step - loss: 1813.5785
Epoch 2/10
1/1 [==============================] - 0s 444us/step - loss: 3997.2852
Epoch 3/10
1/1 [==============================] - 0s 392us/step - loss: 8810.5635
Epoch 4/10
1/1 [==============================] - 0s 349us/step - loss: 19419.8730
Epoch 5/10
1/1 [==============================] - 0s 315us/step - loss: 42804.6797
Epoch 6/10
1/1 [==============================] - 0s 309us/step - loss: 94348.9844
Epoch 7/10
1/1 [==============================] - 0s 365us/step - loss: 207961.6875
Epoch 8/10
1/1 [==============================] - 0s 414us/step - loss: 458384.1875
Epoch 9/10
1/1 [==============================] - 0s 494us/step - loss: 1010359.8125
Epoch 10/10
1/1 [==============================] - 0s 347us/step - loss: 2227010.5000
CodePudding user response:
I tried to change some configurations, and the single biggest change was changing the learning rate from the default 0.01 to 0.001. To do that change
model.compile(optimizer="sgd",.....)
to
model.compile(optimizer=tf.keras.optimizers.SGD(learning_rate=0.001),.....
It uses the same optimizer, but allows you to set a learning rate.
Too big a learning rate will make you shoot over the local minima and might make your loss explode. Learning rate is a good place to start tweaking when your loss explodes.
CodePudding user response:
The problem is not about max
value being 19
or 20
.
Use 2 neurons instead of 1 in the Dense layer like below:
model = tf.keras.Sequential([keras.layers.Dense(units=2, input_shape=[1])])
Maybe 1 neuron can't handle that regression function.