2016-12-06 154 views
0

問題:我需要訓練一個分類器(在matlab中)來分類多個信號噪聲水平。Sklearn支持向量機與Matlab SVM

所以我在matlab中使用fitcecoc訓練了一個多類SVM並獲得了92%的精度。

然後,我在python中使用sklearn.svm.svc訓練了多類SVM,但似乎是我擺弄了參數,我無法達到超過69%的準確度。

30%的數據被阻止並用於驗證培訓。混淆矩陣可以在下面看到。

Matlab confusion matrix

Python confusion matrix

因此,如果任何人有一定的經驗或建議與svm.svc多類培訓,並可以在我的代碼中看到一個問題,或者有什麼建議,將不勝感激。

Python代碼:

import numpy as np 
from sklearn import svm 
from sklearn.model_selection import cross_val_score 
from sklearn.model_selection import train_test_split 
#from sklearn import preprocessing 

#### SET fitting parameters here 
C = 100 
gamma = 1e-8 

#### SET WEIGHTS HERE 
C0_Weight = 1*C 
C1_weight = 1*C 
C2_weight = 1*C 
C3_weight = 1*C 
C4_weight = 1*C 
##### 


X = np.genfromtxt('data/features.csv', delimiter=',') 
Y = np.genfromtxt('data/targets.csv', delimiter=',') 

print 'feature data is of size: ' + str(X.shape) 
print 'target data is of size: ' + str(Y.shape) 

# SPLIT X AND Y INTO TRAINING AND TEST SET 
test_size = 0.3 
X_train, x_test, Y_train, y_test = train_test_split(X, Y,   
... test_size=test_size, random_state=0) 

svc = svm.SVC(C=C,kernel='rbf', gamma=gamma, class_weight = {0:C0_Weight, 
... 1:C1_weight, 2:C2_weight, 3:C3_weight, 4:C4_weight},cache_size = 1000) 

svc.fit(X_train, Y_train) 
scores = cross_val_score(svc, X_train, Y_train, cv=10) 
print scores 
print("Accuracy: %0.2f (+/- %0.2f)" % (scores.mean(), scores.std() * 2)) 

Out = svc.predict(x_test) 

np.savetxt("data/testPredictions.csv", Out, delimiter=",") 
np.savetxt("data/testTargets.csv", y_test, delimiter=",") 

# calculate accuracy in test data 
Hits = 0 
HitsOverlap = 0 
for idx, val in enumerate(Out): 
    Hits += int(y_test[idx]==Out[idx]) 
    HitsOverlap += int(y_test[idx]==Out[idx]) + int(y_test[idx]== 
    ... (Out[idx]-1)) + int(y_test[idx]==(Out[idx]+1)) 

print "Accuracy in testset: ", Hits*100/(11595*test_size) 
print "Accuracy in testset w. overlap: ", HitsOverlap*100/(11595*test_size) 

那些好奇我是怎麼得到的參數,他們被發現與GridSearchCV(並增加了精確度從40%〜69)

任何幫助或建議非常讚賞。

回答