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我用hyperopt搜索SVM分類器的最佳參數,但Hyperopt表示最好的'內核'是'0'。 {'kernel':'0'}顯然是不合適的。Hyperopt解決的最佳參數不適用
有沒有人知道它是由我的錯還是一袋hyperopt造成的?
代碼如下。
from hyperopt import fmin, tpe, hp, rand
import numpy as np
from sklearn.metrics import accuracy_score
from sklearn import svm
from sklearn.cross_validation import StratifiedKFold
parameter_space_svc = {
'C':hp.loguniform("C", np.log(1), np.log(100)),
'kernel':hp.choice('kernel',['rbf','poly']),
'gamma': hp.loguniform("gamma", np.log(0.001), np.log(0.1)),
}
from sklearn import datasets
iris = datasets.load_digits()
train_data = iris.data
train_target = iris.target
count = 0
def function(args):
print(args)
score_avg = 0
skf = StratifiedKFold(train_target, n_folds=3, shuffle=True, random_state=1)
for train_idx, test_idx in skf:
train_X = iris.data[train_idx]
train_y = iris.target[train_idx]
test_X = iris.data[test_idx]
test_y = iris.target[test_idx]
clf = svm.SVC(**args)
clf.fit(train_X,train_y)
prediction = clf.predict(test_X)
score = accuracy_score(test_y, prediction)
score_avg += score
score_avg /= len(skf)
global count
count = count + 1
print("round %s" % str(count),score_avg)
return -score_avg
best = fmin(function, parameter_space_svc, algo=tpe.suggest, max_evals=100)
print("best estimate parameters",best)
輸出低於。
best estimate parameters {'C': 13.271912841932233, 'gamma': 0.0017394328334592358, 'kernel': 0}
哦,我不知道這是已被棄用使用'sklearn.cross_validation'。你的指導非常有幫助,我必須能夠獲得合適的內核價值。非常感謝。 –
@橫尾修平是的,如果你使用v 0.18或更高版本,當你使用'cross_validation'時,你會得到一個警告。 –