df_unique = df.drop_duplicates()- 保留唯一值：df_unique = df.drop_duplicates(subset=['column1', 'column2'])通过以上步骤，我们可以系统地处理数据集中的缺失值、异常值和重复数据，为后续的数据分析和模型构建打下坚实的基础。在实际操作中，选择最适合特定数据集和分析需求的方法至关重要。#python数据...
max_sigma=30, num_sigma=10, threshold=.1) log_blobs[:, 2] = sqrt(2) * log_blobs[:, 2] # Compute radius in the 3rd column dog_blobs = blob_dog(im_gray, max_sigma=30, threshold=0.1
isft.threshold_)defcount_stat(vector):# Because it is'0'and'1',we can run a count statistic.unique,counts=np.unique(vector,return_counts=True)returndict(zip(unique,counts))
# Return missing valuesairquality.isna()我们还可以将isna方法与sum方法链接起来,该方法将返回数据框架中每列缺失值的细分。# Get summary of missingnessairquality.isna().sum()我们注意到CO2列是唯一缺少值的列。利用可视化发现缺失数据的...
degree =80#Definearangeof valuesforlambdalambda_reg_values = np.linspace(0.01,0.99,100)forlambda_reginlambda_reg_values:#For each value of lambda, compute build model and compute performance for lambda_reg in lambda_reg_values:X_train = np.column_stack([np.power(x_train,i)foriinrange(0,...
pivot_table = data.pivot_table(index='A', columns='B', values='C')pivot_table.plot(kind='bar')plt.show() 数据清洗 - 去除空格和特殊字符 # 去除空格data['ColumnName'].str.strip()# 去除特殊字符data['ColumnName'] = data['ColumnName'].str.replace(r'[^a-zA-Z0-9]', '') 使用...
p = plt.boxplot(df['col1'].values,notch=True) outlier = p['fliers'][0].get_ydata() plt.show() len(outlier) 3. 数据标准化 3.1 离差标准化数据(区间缩放) # 自定义离差标准化函数 def MinMaxScale(data): data = (data-data.min())/(data-data.max()) ...
tz_convert tz_localize unique unstack update 49. value_counts values var view where 50. xs 两者同名的方法有181个,另各有30个不同名的: 1. >>> A,B = [_ for _ in dir(pd.DataFrame) if 'a'<=_[0]<='z'],[_ for _ in dir(pd.Series) if 'a'<=_[0]<='z'] 2. >>> len(...
import numpy as np import matplotlib.path as mpath # 数据准备 species = df['species'].unique() data = [] # 只选择数值列(排除 species 列) numeric_columns = df.columns[:-1] for s in species: data.append(df[df['species'] == s][numeric_columns].mean().values) # 将 data 列表转换...
# 各国家的客户数data.groupby(data['Country'])['CustomerID'].nunique().sort_values(ascending=False) 输出结果: CountryUnitedKingdom3921Germany94France87Spain30Belgium25Switzerland21Portugal19Italy14Finland12Austria11Norway10ChannelIslands9Denmark9Australia9Netherlands9Cyprus8Japan8Sweden8Poland6Unspecified4Gr...