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I basically want to add a colorbar at each of the subplots in the code below (link to code ). My attempts add all color bars at the end of the loop in the last subplot. 

print(__doc__)

import matplotlib.pyplot as plt
from sklearn.datasets import fetch_mldata
from sklearn.neural_network import MLPClassifier

mnist = fetch_mldata("MNIST original")
# rescale the data, use the traditional train/test split
X, y = mnist.data / 255., mnist.target
X_train, X_test = X[:60000], X[60000:]
y_train, y_test = y[:60000], y[60000:]

# mlp = MLPClassifier(hidden_layer_sizes=(100, 100), max_iter=400, alpha=1e-4,
#                     solver='sgd', verbose=10, tol=1e-4, random_state=1)
mlp = MLPClassifier(hidden_layer_sizes=(50,), max_iter=10, alpha=1e-4,
                solver='sgd', verbose=10, tol=1e-4, random_state=1,
                learning_rate_init=.1)

mlp.fit(X_train, y_train)
print("Training set score: %f" % mlp.score(X_train, y_train))
print("Test set score: %f" % mlp.score(X_test, y_test))

fig, axes = plt.subplots(4, 4)
# use global min / max to ensure all weights are shown on the same scale
vmin, vmax = mlp.coefs_[0].min(), mlp.coefs_[0].max()
for coef, ax in zip(mlp.coefs_[0].T, axes.ravel()):
ax.matshow(coef.reshape(28, 28), cmap=plt.cm.gray, vmin=.5 * vmin,
           vmax=.5 * vmax)
ax.set_xticks(())
ax.set_yticks(())

plt.show()

UPDATE: based on the link in the comment below, here is the code which adds the colorbar at the right of the diagram

fig, axes = plt.subplots(4, 4)
# use global min / max to ensure all weights are shown on the same scale
vmin, vmax = mlp.coefs_[0].min(), mlp.coefs_[0].max()
for coef, ax in zip(mlp.coefs_[0].T, axes.ravel()):
    im = ax.matshow(coef.reshape(28, 28), cmap=plt.cm.gray, vmin=.5 * vmin, vmax=.5 * vmax)
    ax.set_xticks(())
    ax.set_yticks(())

fig.subplots_adjust(right=0.8)
cbar_ax = fig.add_axes([0.85, 0.15, 0.05, 0.7])
fig.colorbar(im, cax=cbar_ax)

plt.show()
user1571823
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  • The code does not show any attempt to place the colorbar. Also, there are a lot of questions on SO about placing the colorbar, but the question does not state in how far they have not helped. E.g. [this question](https://stackoverflow.com/questions/13784201/matplotlib-2-subplots-1-colorbar?rq=1). – ImportanceOfBeingErnest Aug 29 '17 at 08:57
  • I didn't include my attempt to add the colorbar because it was wrong. But thanks for the link, it does exactly what I need. I'll update my question with the code to add the colorbar. – user1571823 Aug 30 '17 at 09:00

0 Answers0