def kmeans_classification_builder(centroid_func, x_train, x_test, y_train,
y_test):
# plot some train data
N = 25
l = int(np.ceil(np.sqrt(N)))
im = np.zeros((10 * l, 10 * l))
for m in range(l):
for n in range(l):
if (m * l + n < N):
im[10 * m:10 * m + 8,
10 * n:10 * n + 8] = x_train[m * l + n].reshape([8, 8])
plt.imsave('plots/digits.png', im, cmap='Greys')
n_cluster = 10
classifier = KMeansClassifier(n_cluster=n_cluster, max_iter=100, e=1e-6)
classifier.fit(x_train, y_train, centroid_func)
y_hat_test = classifier.predict(x_test)
# print(y_test[0])
# print(len(y_test))
assert y_hat_test.shape == y_test.shape, \
'y_hat_test and y_test should have same shape'
print(
'[*] Prediction accuracy of K-means classifier with {} cluster is {}'.
format(n_cluster, np.mean(y_hat_test == y_test)))
def chooseK(data_X,data_Y):
best_rd=0
best_k=0
for k in range(1,100):
clf = KMeansClassifier(k)
clf.fit(data_X)
labels = clf._labels
a=0
b=0
c=0
d=0
for j in range(len(data_Y)-1,0,-1):
for i in range(0,j):
if data_Y[i]==data_Y[j] and labels[i]==labels[j]:
a+=1
elif data_Y[i]==data_Y[j] and labels[i]!=labels[j]:
b+=1
elif data_Y[i]!=data_Y[j] and labels[i]==labels[j]:
c+=1
else:
d+=1
rd=2*(a+d)/(len(data_Y)*(len(data_Y)-1))
print("rd ",rd,"k ",k)
if rd>best_rd:
best_rd=rd
best_k=k
return best_rd,best_k
def getkmeansresult(k, data_X, data_od):
clf = KMeansClassifier(k)
clf.fit(data_X, data_od)
cents = clf._centroids
labels = clf._labels
flag = True
for i in range(k):
index = np.nonzero(labels == i)[0]
x0 = data_X[index, 0]
x1 = data_X[index, 1]
y_i = i
tmpsum = 0
for j in range(len(x0)):
tmpl = np.math.sqrt(
np.power(cents[i, 0] - x0[j], 2) +
np.power(cents[i, 1] - x1[j], 2))
tmpsum += data_od[index, 0][j]
if tmpl > 3000:
flag = False
break
if tmpsum > 4000:
flag = False
if flag == False:
break
return flag, clf
def kmeans_classification():
x_train, x_test, y_train, y_test = load_digits()
# plot some train data
N = 25
l = int(np.ceil(np.sqrt(N)))
#print(l)
im = np.zeros((10 * l, 10 * l))
for m in range(l):
for n in range(l):
if (m * l + n < N):
im[10 * m:10 * m + 8,
10 * n:10 * n + 8] = x_train[m * l + n].reshape([8, 8])
plt.imsave('plots/digits.png', im, cmap='Greys')
n_cluster = 30
classifier = KMeansClassifier(n_cluster=n_cluster, max_iter=100, e=1e-6)
classifier.fit(x_train, y_train)
y_hat_test = classifier.predict(x_test)
assert y_hat_test.shape == y_test.shape, \
'y_hat_test and y_test should have same shape'
print('Prediction accuracy of K-means classifier with {} cluster is {}'.
format(n_cluster, np.mean(y_hat_test == y_test)))
linear_classifier = LogisticRegression()
linear_classifier.fit(x_train, y_train)
y_hat_test = linear_classifier.predict(x_test)
print('Accuracy of logistic regression classifier is {}'.format(
np.mean(y_hat_test == y_test)))
KNNClassifier = KNeighborsClassifier()
KNNClassifier.fit(x_train, y_train)
y_hat_test = KNNClassifier.predict(x_test)
print('Accuracy of Nearest Neighbour classifier is {}'.format(
np.mean(y_hat_test == y_test)))
np.savez('results/k_means_classification.npz',
y_hat_test=y_hat_test,
y_test=y_test,
centroids=classifier.centroids,
centroid_labels=classifier.centroid_labels)
def fit(self, X):
m = X.shape[0]
self._clusterAssment = np.zeros((m, 2))
centroid0 = np.mean(X, axis=0).tolist()
cenList = [centroid0]
for j in range(m): # 计算每个样本点与质心之间初始的平方误差
self._clusterAssment[j,
1] = self._calEDist(np.asarray(centroid0),
X[j, :])**2
while (len(cenList) < self._k):
lowestSSE = np.inf
for i in range(len(cenList)):
index_all = self._clusterAssment[:, 0] # 取出样本所属簇的索引值
value = np.nonzero(index_all == i) # 取出所有属于第i个簇的索引点
pstInCurrCluster = X[value[0], :] # 取出属于第i个簇的所有样本点
clf = KMeansClassifier(k=2)
clf.fit(pstInCurrCluster)
centroidMat, splitClustAss = clf._centroids, clf._clusterAssment
sseSplit = sum(splitClustAss[:, 1])
index_all = self._clusterAssment[:, 0]
value = np.nonzero(index_all == i)
sseNotSplit = sum(self._clusterAssment[value[0], 1])
if (sseSplit + sseNotSplit) < lowestSSE:
bestCentToSplit = i
bestNewCents = centroidMat
bestClustAss = splitClustAss.copy()
lowestSSE = sseSplit + sseNotSplit
# 该簇被划分为两个子簇后，其中一个子簇的索引变为原簇的索引
# 另一个子簇的索引变为len(cenList)，然后存入cenList。
bestClustAss[np.nonzero(bestClustAss[:, 0] == 1)[0],
0] = len(cenList)
bestClustAss[np.nonzero(bestClustAss[:, 0] == 0)[0],
0] = bestCentToSplit
cenList[bestCentToSplit] = bestNewCents[0, :].tolist()
cenList.append(bestNewCents[1, :]).tolist()
self._clusterAssment[np.nonzero(
self._clusterAssment[:, 0] ==
bestCentToSplit)[0], :] = bestClustAss
self._labels = self._clusterAssment[:, 0]
self._sse = sum(self._clusterAssment[:, 1])
self._centroids = np.asarray(cenList)
def get_cluster(starttime, stoptime, k):
'''
# la focntion qui effectue l'algorithme Kmeans
# retourne sur un periode et k donne, la datafrme des sation avec leur numeros de cluster.
'''
df = get_pandas_df(starttime, stoptime)
df_origin = df[1]
df = df[0]
data_X = np.array(df).astype(np.float)
clf = KMeansClassifier(k)
clf.fit(data_X)
centroids = clf._centroids
labels = clf._labels
df_origin["label_kmeans"] = labels.astype('int')
plt.scatter(df['lon'], df['lat'], c=labels, s=50, alpha=0.5)
plt.scatter(centroids[:, 0], centroids[:, 1], c='red', s=50)
plt.show()
return df_origin, centroids
"""
import pandas as pd
import numpy as np
from kmeans import KMeansClassifier
import matplotlib.pyplot as plt
#加载数据集，DataFrame格式，最后将返回为一个matrix格式
def loadDataset(infile):
df = pd.read_csv(infile, sep='\t', header=0, dtype=str, na_filter=False)
return np.array(df).astype(np.float)
if __name__=="__main__":
data_X = loadDataset(r"data/testSet.txt")
k = 3
clf = KMeansClassifier(k)
clf.fit(data_X)
cents = clf._centroids
labels = clf._labels
sse = clf._sse
colors = ['b','g','r','k','c','m','y','#e24fff','#524C90','#845868']
for i in range(k):
index = np.nonzero(labels==i)[0]
x0 = data_X[index, 0]
x1 = data_X[index, 1]
y_i = i
for j in range(len(x0)):
plt.text(x0[j], x1[j], str(y_i), color=colors[i], \
fontdict={'weight': 'bold', 'size': 6})
plt.scatter(cents[i,0],cents[i,1],marker='x',color=colors[i],\
linewidths=7)
from kmeans import KMeansClassifier
def load_data(path):
df = pd.read_csv(path, sep="\t", header=0, dtype=str, na_filter=False)
return np.array(df).astype(np.float)
if __name__ == "__main__":
project_dir = os.path.dirname(os.path.realpath(__file__))
data = load_data(os.path.join(project_dir, 'data', 'test.txt'))
k = 3
classifier = KMeansClassifier(k)
classifier.fit(data)
centers = classifier._centroids
labels = classifier._labels
sse = classifier._sse
print(labels)
print(sse)
colors = [
'b', 'g', 'r', 'k', 'c', 'm', 'y', '#e24fff', '#524C90', '#845868'
]
for i in range(k):
index = np.nonzero(labels == i)[0]
x = data[index, 0]
y = data[index, 1]
for j in range(len(x)):
plt.text(x[j],
y[j],