Why my svm.SVC.fit( ) (linear kernal) run so long time?

Question

I am using sklearn.svm.SVC( ) to train & test my dataset. 80% are used for training, 20% are used for testing.

Here is my Python code:

data = pd.read_csv(trainPath, header=0)

X = data.iloc[:, 5:17].values
y = data.iloc[:, 17:18].values

X_train, X_test, y_train, y_test = train_test_split(X, y, test_size=0.2, random_state=0)

print(X_train.dtype, y_train.dtype)  # float64 int64

clf = svm.SVC(kernel='linear').fit(X_train, y_train.ravel())
print('done')

y_pred = clf.predict(X_test)

print("Accuracy:", metrics.accuracy_score(y_test, y_pred))
print("Precision:", metrics.precision_score(y_test, y_pred))
print("Recall:", metrics.recall_score(y_test, y_pred))
tn, fp, fn, tp = confusion_matrix(y_test, y_pred).ravel()
print(tn, fp, fn, tp)

For data.shape = 30,000 x 13, it runs around 15 mins.

For data.shape = 130,000 x 13, it runs more than 1 hour.

Why it runs so long time, I don't think it is normal.

• i5, 2.8GHz, 16.0 GB memory

Answer 1

From scikit-learn documentation:

The implementation is based on libsvm. The fit time scales at least quadratically with the number of samples and may be impractical beyond tens of thousands of samples. For large datasets consider using sklearn.linear_model.LinearSVC or sklearn.linear_model.SGDClassifier instead, possibly after a sklearn.kernel_approximation.Nystroem transformer.

Yo can change

clf = svm.SVC(kernel='linear').fit(X_train, y_train.ravel())

by

from sklearn.svm import LinearSVC
clf = LinearSVC(random_state=0, tol=1e-5)
clf.fit(X_train, y_train.ravel())