The default value of gamma will change from 'auto' to 'scale' in version 0.22 to account better for unscaled features.

實現《python數據科學手冊》代碼時出現如下警告：

py:196: FutureWarning: The default value of gamma will change from 'auto' to 'scale' in version 0.22 to account better for unscaled features. Set gamma explicitly to 'auto' or 'scale' to avoid this warning.
  "avoid this warning.", FutureWarning

出現該警告的源碼如下：

clf = SVC(kernel='rbf', C=1E6)
clf.fit(X, y)

解決方案：

根據 warning 的提示，在 C=1E6 后加上 , gamma='auto'， 即

clf = SVC(kernel='rbf', C=1E6, gamma='auto')
clf.fit(X, y)