Beispiel #1
0
def demo():
    """ _test_knn
    
    This demo tests the KNNClassifier on a file stream, which gives
    instances coming from a SEA generator. 
    
    The test computes the performance of the KNNClassifier as well as
    the time to create the structure and classify max_samples (5000 by 
    default) instances.
    
    """
    stream = FileStream("https://raw.githubusercontent.com/scikit-multiflow/streaming-datasets/"
                        "master/sea_big.csv")

    train = 200
    X, y = stream.next_sample(train)
    # t = OneHotToCategorical([[10, 11, 12, 13],
    #                         [14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35,
    #                          36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53]])
    # t2 = OneHotToCategorical([[10, 11, 12, 13],
    #                         [14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35,
    #                          36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53]])
    start = timer()
    knn = KNNClassifier(n_neighbors=8, max_window_size=2000, leaf_size=40)
    # pipe = Pipeline([('one_hot_to_categorical', t), ('KNNClassifier', knn)])

    # compare = KNeighborsClassifier(n_neighbors=8, algorithm='kd_tree', leaf_size=40, metric='euclidean')

    # pipe2 = Pipeline([('one_hot_to_categorical', t2), ('KNNClassifier', compare)])

    # pipe.fit(X, y)
    # pipe2.fit(X, y)
    knn.partial_fit(X, y)
    # compare.fit(X, y)

    n_samples = 0
    max_samples = 5000
    my_corrects = 0
    # compare_corrects = 0

    while n_samples < max_samples:
        X, y = stream.next_sample()
        # my_pred = pipe.predict(X)
        my_pred = knn.predict(X)
        # compare_pred = pipe2.predict(X)
        # compare_pred = compare.predict(X)
        if y[0] == my_pred[0]:
            my_corrects += 1
        # if y[0] == compare_pred[0]:
        #     compare_corrects += 1
        n_samples += 1

    end = timer()

    print('Evaluation time: ' + str(end-start))
    print(str(n_samples) + ' samples analyzed.')
    print('My performance: ' + str(my_corrects/n_samples))
##EKSPERYENT 1
adwin_param = [0.002, 0.005, 0.01]
ddm_param = [3, 5, 7]
ks_param1 = [100, 150, 200]
ks_param2 = [30, 50, 100]
ph_param1 = [25, 50, 75]
ph_param2 = [0.005, 0.01, 0.02]

knn = KNNClassifier()

stream = driftStreams[0]

for i in range(0, 3):
    trainX, trainY = stream.next_sample(2000)
    knn.partial_fit(trainX, trainY)

    adwin = ADWIN(delta=adwin_param[i])
    ddm = DDM(out_control_level=ddm_param[i])
    kswin1 = KSWIN(window_size=ks_param1[i])
    # kswin2 = KSWIN(stat_size=ks_param2[i])
    ph1 = PageHinkley(threshold=ph_param1[i])
    ph2 = PageHinkley(delta=ph_param2[i])

    adwin_results = []
    ddm_results = []
    kswin1_results = []
    kswin2_results = []
    ph1_results = []
    ph2_results = []
def test_knn():
    stream = SEAGenerator(random_state=1)

    learner = KNNClassifier(n_neighbors=8, max_window_size=2000, leaf_size=40)
    cnt = 0
    max_samples = 5000
    predictions = array('i')
    correct_predictions = 0
    wait_samples = 100
    X_batch = []
    y_batch = []

    while cnt < max_samples:
        X, y = stream.next_sample()
        X_batch.append(X[0])
        y_batch.append(y[0])
        # Test every n samples
        if (cnt % wait_samples == 0) and (cnt != 0):
            predictions.append(learner.predict(X)[0])
            if y[0] == predictions[-1]:
                correct_predictions += 1
        learner.partial_fit(X, y)
        cnt += 1

    expected_predictions = array('i', [
        1, 1, 1, 0, 1, 1, 0, 0, 0, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
        1, 1, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1, 0, 1, 0, 0, 1, 0,
        1
    ])
    assert np.alltrue(predictions == expected_predictions)

    expected_correct_predictions = 49
    assert correct_predictions == expected_correct_predictions

    expected_info = "KNNClassifier(leaf_size=40, max_window_size=2000, " \
                    "metric='euclidean', n_neighbors=8)"
    info = " ".join([line.strip() for line in learner.get_info().split()])
    assert info == expected_info

    learner.reset()
    info = " ".join([line.strip() for line in learner.get_info().split()])
    assert info == expected_info

    X_batch = np.array(X_batch)
    y_batch = np.array(y_batch)
    learner.fit(X_batch[:4500], y_batch[:4500], classes=[0, 1])
    predictions = learner.predict(X_batch[4501:4550])

    expected_predictions = array('i', [
        1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0, 1, 0, 1, 1,
        1, 1, 0, 0, 1, 0, 0, 1, 1, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 1,
        0
    ])
    assert np.alltrue(predictions == expected_predictions)

    correct_predictions = sum(predictions == y_batch[4501:4550])
    expected_correct_predictions = 49
    assert correct_predictions == expected_correct_predictions

    assert type(learner.predict(X)) == np.ndarray
    assert type(learner.predict_proba(X)) == np.ndarray
Beispiel #4
0
class LabelPredict:
    def __init__(self, texts: list):
        self.tokenizer = TfidfVectorizer()
        self.tokenizer.fit(texts)

        self.labels_sent = {"POSITIVE": np.array([1, 0, 0]), "NEUTRAL": np.array([0, 1, 0]),
                            "NEGATIVE": np.array([0, 0, 1])}
        self.labels_sent = {"POSITIVE": 0, "NEUTRAL": 1,
                            "NEGATIVE": 2}
        self.reverse_sent = {0: {"POSITIVE": True, "NEUTRAL": False,
                                 "NEGATIVE": False},
                             1: {"POSITIVE": False, "NEUTRAL": True,
                                 "NEGATIVE": False},
                             2: {"POSITIVE": False, "NEUTRAL": False,
                                 "NEGATIVE": True}}

        self.labels_relevance = ["Irrelevant"]
        self.labels = []
        self.lcc = ClassifierChain(SGDClassifier(max_iter=100, loss='log', random_state=1))
        self.clrel = KNNClassifier()
        self.clsent = KNNClassifier()

    def _labels2array(self, labeldict: dict):
        target = []
        for label in self.labels:
            if label in labeldict and labeldict[label] == True:
                target.append(1)
            else:
                target.append(0)
        return np.array(target)

    def retrain(self, labeled_tweets: list):
        labels = set()
        for tweet in labeled_tweets:
            if "labels" in tweet and len(tweet["labels"]) > 0:
                labels.update([l for l in tweet["labels"] if not (l in self.labels_sent or l in self.labels_relevance)])
        self.labels = list(labels)
        assert "Irrelevant" not in self.labels, "Something went wrong"
        self.lcc = ClassifierChain(SGDClassifier(max_iter=100, loss='log', random_state=1))
        self.clrel = KNNClassifier()
        self.clsent = KNNClassifier()
        X, y, ys, yr = [], [], [], []
        for tweet in labeled_tweets:
            if "labels" in tweet and len(tweet["labels"]) > 0:
                X.append(tweet["tweet"])
                y.append(self._labels2array(tweet["labels"]))
                sls = [l for l, v in tweet["labels"].items() if l in self.labels_sent and v]
                if len(sls) == 1:
                    ys.append(self.labels_sent[sls[0]])
                else:
                    ys.append(self.labels_sent["NEUTRAL"])
                if self.labels_relevance[0] in tweet["labels"] and tweet["labels"][self.labels_relevance[0]]:
                    yr.append(1)
                else:
                    yr.append(0)

        X = np.array(self.tokenizer.transform(X).todense())
        y = np.array(y)
        ys = np.array(ys)
        yr = np.array(yr)
        self.clsent.fit(X, ys)
        print("Trained Sentiment Classifier")
        self.clrel.fit(X, yr)
        print("Trained Relevance Classifier")
        X2, y2 = [], []
        for Xe, ye in zip(X, y):
            if ye.sum() > 0:
                X2.append(Xe)
                y2.append(ye)
        X = np.array(X2)
        y = np.array(y2)
        self.lcc.fit(X, y)
        print("Trained Catecorical Classifier")

    def predict(self, text: str):
        X = np.array(self.tokenizer.transform([text]).todense()).reshape((1, -1))
        predicted = self.lcc.predict(X)
        labels_add = {label: bool(value) for label, value in zip(self.labels, predicted.flatten())}
        sent_pred = self.clsent.predict(X)
        labels_add.update(self.reverse_sent[sent_pred.flatten()[0]])

        assert "POSITIVE" in labels_add, "Klassifikation nicht eindeutig"

        if self.clrel.predict(X) == np.array([1]):
            labels_add[self.labels_relevance[0]] = True
        else:
            labels_add[self.labels_relevance[0]] = False
        return labels_add

    def train_item(self, tweet):
        text = tweet["tweet"]
        labeldict = tweet["labels"]
        for l in labeldict:
            if l not in self.labels and l not in self.labels_relevance and l not in self.labels_sent:
                print("RETRAIN!")
                return False
        y = self._labels2array(labeldict).reshape((1, -1))
        X = np.array(self.tokenizer.transform([text]).todense()).reshape((1, -1))

        sls = [l for l, v in labeldict.items() if l in self.labels_sent and v]
        if len(sls) == 1:
            ys = self.labels_sent[sls[0]]
        else:
            ys = self.labels_sent["NEUTRAL"]
        ys = np.array([ys])
        if self.labels_relevance[0] in labeldict and labeldict[self.labels_relevance[0]]:
            yr = np.array([1])
        else:
            yr = np.array([0])
        if y.sum() > 0:
            self.lcc.partial_fit(X, y)
        if yr.sum() > 0:
            self.clrel.partial_fit(X, yr)
        if ys.sum() > 0:
            self.clsent.partial_fit(X, ys)
        return True