# 导入内置模块import mathprint(math.sin(math.pi / 2))# 导入自定义模块from mymodule import myfuncmyfunc()# 导入第三方库import numpy as npa = np.array([1, 2, 3])print(a)# 使用 pip 安装第三方库# pip install requestsimport requestsr
from sklearn.metrics import roc_auc_score y_true = np.array([0, 0, 1, 1]) y_scores = np.array([0.1, 0.4, 0.35, 0.8]) roc_auc_score(y_true, y_scores) # 2,ROC曲线 y = np.array([1, 1, 2, 2]) scores = np.array([0.1, 0.4, 0.35, 0.8]) fpr, tpr, thresholds = roc...
1. TPR、FPR&TNR(混淆矩阵) 在二分类问题中,即将实例分成正类(positive)或负类(negative)。对一个二分问题来说,会出现四种情况。如果一个实例是正类并且也被 预测成正类,即为真正类(True positive),如果实例是负类被预测成正类,称之为假正类(False positive)。相应地,如果实例是负类被预测成负类,称之为...
(precision=2) # 在混淆矩阵中每格的概率值 ind_array = np.arange(len(classes)+1) x, y = np.meshgrid(ind_array, ind_array)#生成坐标矩阵 diags = np.diag(cm)#对角TP值 TP_FNs, TP_FPs = [], [] for x_val, y_val in zip(x.flatten(), y.flatten()):#并行遍历 max_index = len...
The negative indexes count backward from the end of the array, but are most commonly used to reference the last element of an array. if crypt.crypt(guess,salt) == password: userInfo = { "user" : user, "pass" : guess, "home" : data[5], "uid" : data[2] , "name" : geco[0...
'nanmedian', 'nanmin', 'nanpercentile', 'nanprod', 'nanstd', 'nansum', 'nanvar', 'nbytes', 'ndarray', 'ndenumerate', 'ndfromtxt', 'ndim', 'ndindex', 'nditer', 'negative', 'nested_iters', 'newaxis', 'nextafter', 'nonzero', 'not_equal', 'nper', 'npv', 'numarray', 'num...
for (int i = index - 1; i >= 0 && mHashes[i] == hash; i--) { if (key.equals(mArray[i])) return i; } // Key not found -- return negative value indicating where a // new entry for this key should go. We use the end of the ...
``` # Python script to download images in bulk from a website import requests def download_images(url, save_directory): response = requests.get(url) if response.status_code == 200: images = response.json() # Assuming the API returns a JSON array of image URLs for index, image_url in...
X_pred = model.predict(np.array(X_test)) X_pred = pd.DataFrame(X_pred, columns=X_test.columns) X_pred.index = X_test.index threshod =0.3 scored = pd.DataFrame(index=X_test.index) scored['Loss_mae'] = np.mean(np.abs(X...
异常检测(Anomaly detection)是机器学习的常见应用,其目标是识别数据集中的异常或不寻常模式。尽管通常被归类为非监督学习问题,异常检测却具有与监督学习相似的特征。在异常检测中,我们通常处理的是未标记的数据,即没有明确的标签指示哪些样本是异常的。相反,算法需要根据数据本身的特征来确定异常。这使得异常检测成为一项...