#!/usr/bin/env python3 # -*- coding: utf-8 -*- """ Created on Tue Nov 6 23:44:54 2018@author: lilong """ import pandas as pd import numpy as np# 通過行標簽索引行數(shù)據(jù) index可以為整數(shù) data = [[1,2,3],[4,5,6]] index = [0,1] columns=['a','b','c'] df = pd.DataFrame(data=data, index=index, columns=columns) print (df,'\n') print (df.loc[0],'\n') print (df.loc[1]) print('.................')# 行標簽索引 index為字符 data = [[1,2,3],[4,5,6]] index = ['d','e'] columns=['a','b','c'] df = pd.DataFrame(data=data, index=index, columns=columns) print (df,'\n') print (df.loc['d']) print('.................')# 多行獲取 data = [[1,2,3],[4,5,6]] index = ['d','e'] columns=['a','b','c'] df = pd.DataFrame(data=data, index=index, columns=columns) print (df,'\n') print (df.loc['d':]) print('.................')# 索引某行某列 data = [[1,2,3],[4,5,6]] index = ['d','e'] columns=['a','b','c'] df = pd.DataFrame(data=data, index=index, columns=columns) print (df,'\n') print (df.loc['d',['b','c']]) print('.................')# 索引某列 data = [[1,2,3],[4,5,6]] index = ['d','e'] columns=['a','b','c'] df = pd.DataFrame(data=data, index=index, columns=columns) print (df,'\n') print (df.loc[:,['c']]) print('.................')# iloc通過行號索引 data = [[1,2,3],[4,5,6]] index = ['d','e'] columns=['a','b','c'] df = pd.DataFrame(data=data, index=index, columns=columns) print (df,'\n') print (df.iloc[1]) print('.................')# iloc通過行號多行索引 data = [[1,2,3],[4,5,6]] index = ['d','e'] columns=['a','b','c'] df = pd.DataFrame(data=data, index=index, columns=columns) print (df,'\n') print (df.iloc[0:]) print('.................')# iloc索引列 data = [[1,2,3],[4,5,6]] index = ['d','e'] columns=['a','b','c'] df = pd.DataFrame(data=data, index=index, columns=columns) print (df,'\n') print (df.iloc[:,[1]]) print('.................')data = [[1,2,3],[4,5,6]] index = ['d','e'] columns=['a','b','c'] df = pd.DataFrame(data=data, index=None, columns=columns) print (df,'\n') print (df.iloc[:,[1]],'\n') tt=df.iloc[:,[1]] print(tt.values)''' # 索引列數(shù)據(jù)時 如下操作會出錯: # KeyError: 'the label [a] is not in the [index]' data = [[1,2,3],[4,5,6]] index = ['d','e'] columns=['a','b','c'] df = pd.DataFrame(data=data, index=index, columns=columns) print (df,'\n') print (df.loc['a']) '''# DataFrame類型轉(zhuǎn)換成Numpy中array類型的三種方法 data = [[1,2,3],[4,5,6]] index = ['d','e'] columns=['a','b','c'] df = pd.DataFrame(data=data, index=None, columns=columns) print (df,'\n') print(df.values,'\n') print(df.as_matrix(),'\n') print(np.array(df),'\n')

運行：

a b c 0 1 2 3 1 4 5 6 a 1 b 2 c 3 Name: 0, dtype: int64 a 4 b 5 c 6 Name: 1, dtype: int64 .................a b c d 1 2 3 e 4 5 6 a 1 b 2 c 3 Name: d, dtype: int64 .................a b c d 1 2 3 e 4 5 6 a b c d 1 2 3 e 4 5 6 .................a b c d 1 2 3 e 4 5 6 b 2 c 3 Name: d, dtype: int64 .................a b c d 1 2 3 e 4 5 6 c d 3 e 6 .................a b c d 1 2 3 e 4 5 6 a 4 b 5 c 6 Name: e, dtype: int64 .................a b c d 1 2 3 e 4 5 6 a b c d 1 2 3 e 4 5 6 .................a b c d 1 2 3 e 4 5 6 b d 2 e 5 .................a b c 0 1 2 3 1 4 5 6 b 0 2 1 5 [[2][5]]a b c 0 1 2 3 1 4 5 6 [[1 2 3][4 5 6]] [[1 2 3][4 5 6]] [[1 2 3][4 5 6]] 與50位技術(shù)專家面對面20年技術(shù)見證，附贈技術(shù)全景圖

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