value_counts方法 pandas.DataFrame按照某几列分组并统计:groupby+count pandas.DataFrame按照某列分组并求和 pandas.DataFrame按照某列分组并取出某个小组:groupby+get_group pandas.DataFrame排序 pandas.DataFrame按照行标签或者列标签排序:sort_index方法 pandas.DataFrame按照某列值排序:sort_values方法by参数 pandas....
1.1.3 字典创建DataFrame index表示行索引。如果创建时不指定index,系统会自动生成从0开始的索引。columns为列名,表格内的具体参数值为values importpandasaspdimportnumpyasnpdf=pd.DataFrame({'A':1.,'B':pd.Timestamp('20130102'),'C':pd.Series(1,index=list(range(4)),dtype='float32'),'D':np.array...
#如果要修改列标签,可以通过columns参数进行,与index操作相同 first_df.rename(index={0:"a",1:"b"},inplace=True) print(first_df) print('#3','-'*30) #自定义函数修改,下面是自定义了一个把文本全部转换成大写,并且加上*的函数 #把函数传递给列标签参数columns和行标签参数index就可以对每个标签进行...
pd.crosstab(value1,value2) 传入值为两列,返回两列的对应关系 pandas日期类型(转换为DatetimeIndex): pd.to_datetime DatetimeIndex数据的属性: year,month,weekday 2)透视表: DataFrame.pivot_table([],index=[]) 前面输入需要查看的数据列,后面提供索引 分组与聚合: DataFrame.groupby(by,as_index=False) by:...
getitem()里调用了: ._get_value(-1)方法, 该方法调用了: .index.get_loc(-1)方法. 问题就出在这里了: .index._range.index(-1) '-1' 这个索引键根本就不在s1的索引里. 因为我们的s1的索引是: range(1) 所以程序才会抛出异常: KeyError: -1 ...
[index, name])Iterate over DataFrame rows as namedtuples, with index value as first element of the tuple.DataFrame.lookup(row_labels, col_labels)Label-based “fancy indexing” function for DataFrame.DataFrame.pop(item)返回删除的项目DataFrame.tail([n])返回最后n行DataFrame.xs(key[, axis, level...
columns Out[14]: Index(['color', 'director_name', 'num_critic_for_reviews', 'duration', 'director_facebook_likes', 'actor_3_facebook_likes', 'actor_2_name', 'actor_1_facebook_likes', 'gross', 'genres', 'actor_1_name', 'movie_title', 'num_voted_users', 'cast_total_face...
DataFrame.insert(loc, column, value[, …])在特殊地点插入行 DataFrame.iter()Iterate over infor axis DataFrame.iteritems()返回列名和序列的迭代器 DataFrame.iterrows()返回索引和序列的迭代器 DataFrame.itertuples([index, name])Iterate over DataFrame rows as namedtuples, with index value as first elem...
DataFrame.xs() returns a value error if a non-unique multi-index is used and the level kwarg is called. However, if the level karg is not called, or a tuple is passed the function behaves normally. import sys if sys.version[0] == '2': from StringIO import StringIO if sys.version...
df[0,1] =10;// 0 is the rowIndex, and 1 is the columnIndex. This sets the 0th value in the Ints columns to 10 We can also modify the values in the columns through indexers defined onPrimitiveDataFrameColumnandStringDataFrameColumn: ...