keras/examples/demo_mnist_convnet.py
Francois Chollet 942d5958d4 Fix JAX test.
2023-06-05 13:44:31 -07:00

57 lines
1.5 KiB
Python

import numpy as np
import keras_core
from keras_core import layers
from keras_core.utils import to_categorical
# Model / data parameters
num_classes = 10
input_shape = (28, 28, 1)
# Load the data and split it between train and test sets
(x_train, y_train), (x_test, y_test) = keras_core.datasets.mnist.load_data()
# Scale images to the [0, 1] range
x_train = x_train.astype("float32") / 255
x_test = x_test.astype("float32") / 255
# Make sure images have shape (28, 28, 1)
x_train = np.expand_dims(x_train, -1)
x_test = np.expand_dims(x_test, -1)
print("x_train shape:", x_train.shape)
print(x_train.shape[0], "train samples")
print(x_test.shape[0], "test samples")
# convert class vectors to binary class matrices
y_train = to_categorical(y_train, num_classes)
y_test = to_categorical(y_test, num_classes)
batch_size = 128
epochs = 3
model = keras_core.Sequential(
[
layers.Input(shape=input_shape),
layers.Conv2D(32, kernel_size=(3, 3), activation="relu"),
layers.MaxPooling2D(pool_size=(2, 2)),
layers.Conv2D(64, kernel_size=(3, 3), activation="relu"),
layers.MaxPooling2D(pool_size=(2, 2)),
layers.Flatten(),
layers.Dropout(0.5),
layers.Dense(num_classes, activation="softmax"),
]
)
model.summary()
model.compile(
loss="categorical_crossentropy", optimizer="adam", metrics=["accuracy"]
)
model.fit(
x_train, y_train, batch_size=batch_size, epochs=epochs, validation_split=0.1
)
score = model.evaluate(x_test, y_test, verbose=0)
print("Test loss:", score[0])
print("Test accuracy:", score[1])