alex_bn_lee

摘要： ref: Pandas新增一列并按条件赋值？ 把下图中的 NaN 都赋值为 0 df.loc[条件判断, 'value'] = 0 m = pd.merge(gdf_africa, df_af_mp, how='left', on='country') m.loc[m['value'].isna() 阅读全文

摘要： Suppose we have a dataframe, it has a column of "country". It lists different names of country's names, and for one country maybe it has multiple reco 阅读全文

摘要： ref: R语言——日期时间处理 ref: as.Date: Date Conversion Functions to and from Character ref: Date Formats in R as.Date()it can change a normal string into a da 阅读全文