# View more python learning tutorial on my Youtube and Youku channel!!!

# Youtube video tutorial: https://www.youtube.com/channel/UCdyjiB5H8Pu7aDTNVXTTpcg

# Youku video tutorial: http://i.youku.com/pythontutorial

"""

Please note, this code is only for python 3+. If you are using python 2+, please modify the code accordingly.

"""

from __future__ import print_function

from sklearn.learning_curve import  validation_curve

from sklearn.datasets import load_digits

from sklearn.svm import SVC

import matplotlib.pyplot as plt

import numpy as np

digits = load_digits()

X = digits.data

y = digits.target

param_range = np.logspace(-6, -2.3, 5)

train_loss, test_loss = validation_curve(

        SVC(), X, y, param_name='gamma', param_range=param_range, cv=10,

        scoring='mean_squared_error')

train_loss_mean = -np.mean(train_loss, axis=1)

test_loss_mean = -np.mean(test_loss, axis=1)

plt.plot(param_range, train_loss_mean, 'o-', color="r",

             label="Training")

plt.plot(param_range, test_loss_mean, 'o-', color="g",

             label="Cross-validation")

plt.xlabel("gamma")

plt.ylabel("Loss")

plt.legend(loc="best")

plt.show()