s1ep3-pandas和大熊猫们Pandas一起游戏吧

和大熊猫们(Pandas)一起游API速查：(基于NumPy,SciPy的功能，在其上补充了大量的数据操作（DataManipulation）功能0.上手玩：Why普通的程序员看到一份数据会怎么做InimportcodecsimportrequestsimportnumpyasnpimportscipyasspimportimportcodecsimportrequestsimportnumpyasnpimportscipyasspimportpandasaspdimportdatetimeimportjsonInrr=withcodecs.open('S1EP3_Iris.txt','w',encoding='utf-8')asf:5.1,3.5,1.4,0.2,Iris-4.9,3.0,1.4,0.2,Iris-4.7,3.2,1.3,0.2,Iris-4.6,3.1,1.5,0.2,Iris-5.0,3.6,1.4,0.2,Iris-5.4,3.9,1.7,0.4,Iris-4.6,3.4,1.4,0.3,Iris-5.0,3.4,1.5,0.2,Iris-4.4,2.9,1.4,0.2,Iris-4.9,3.1,1.5,0.1,Iris-5.4,3.7,1.5,0.2,Iris-4.8,3.4,1.6,0.2,Iris-4.8,3.0,1.4,0.1,Iris-,3.0,1.1,0.1,Iris-5.8,4.0,1.2,0.2,Iris-5.7,4.4,1.5,0.4,Iris-5.4,3.9,1.3,0.4,Iris-5.1,3.5,1.4,0.3,Iris-,3.8,1.7,0.3,Iris-5.1,3.8,1.5,0.3,Iris-5.4,3.4,1.7,0.2,Iris-,3.7,1.5,0.4,Iris-,3.6,1.0,0.2,Iris-,3.3,1.7,0.5,Iris-4.8,3.4,1.9,0.2,Iris-5.0,3.0,1.6,0.2,Iris-5.0,3.4,1.6,0.4,Iris-5.2,3.5,1.PAGE5.2,3.5,1.PAGE6,0.2,Iris-,3.4,1.4,0.2,Iris-,3.2,1.6,0.2,Iris-5.4,3.4,1.5,0.4,Iris-,4.1,1.5,0.1,Iris-5.5,4.2,1.4,0.2,Iris-4.9,3.1,1.5,0.1,Iris-5.0,3.2,1.2,0.2,Iris-5.5,3.5,1.3,0.2,Iris-4.9,3.1,1.5,0.1,Iris-,3.0,1.3,0.2,Iris-5.1,3.4,1.5,0.2,Iris-5.0,3.5,1.3,0.3,Iris-,2.3,1.3,0.3,Iris-4.4,3.2,1.3,0.2,Iris-5.0,3.5,1.6,0.6,Iris-5.1,3.8,1.9,0.4,Iris-,3.0,1.4,0.3,Iris-5.1,3.8,1.6,0.2,Iris-,3.2,1.4,0.2,Iris-,3.7,1.5,0.2,Iris-5.8,2.6,4.0,1.2,Iris-5.0,2.3,3.3,1.0,Iris-5.0,2.3,3.3,1.0,Iris-5.1,2.5,3.0,1.1,Iris-5.1,2.5,3.0,1.1,Iris-Inwithwithcodecs.open('S1EP3_Iris.txt','r',encoding='utf-8')asf:lines=f.readlines()forlineinprint5.1,3.5,1.4,0.2,Iris-4.9,3.0,1.4,0.PAGE4.9,3.0,1.4,0.PAGE3,Iris-,3.2,1.3,0.2,Iris-4.6,3.1,1.5,0.2,Iris-5.0,3.6,1.4,0.2,Iris-,3.9,1.7,0.4,Iris-5.0,3.4,1.5,0.2,Iris-4.4,2.9,1.4,0.2,Iris-,3.1,1.5,0.1,Iris-5.4,3.7,1.5,0.2,Iris-,3.4,1.6,0.2,Iris-4.8,3.0,1.4,0.1,Iris-,3.0,1.1,0.1,Iris-,4.0,1.2,0.2,Iris-5.7,4.4,1.5,0.4,Iris-5.4,3.9,1.3,0.4,Iris-5.1,3.5,1.4,0.3,Iris-5.7,3.8,1.7,0.3,Iris-,3.8,1.5,0.3,Iris-5.4,3.4,1.7,0.2,Iris-,3.7,1.5,0.4,Iris-,3.6,1.0,0.2,Iris-,3.3,1.7,0.5,Iris-4.8,3.4,1.9,0.2,Iris-5.0,3.0,1.6,0.2,Iris-5.0,3.4,1.6,0.4,Iris-,3.5,1.5,0.2,Iris-,3.4,1.4,0.2,Iris-,3.2,1.6,0.2,Iris-,3.1,1.6,0.2,Iris-5.4,3.4,1.5,0.4,Iris-,4.1,1.5,0.1,Iris-5.5,4.2,1.4,0.2,Iris-,3.1,1.5,0.1,Iris-5.0,3.2,1.2,0.2,Iris-5.5,3.5,1.3,0.2,Iris-4.9,3.1,1.5,0.1,Iris-,3.0,1.3,0.2,Iris-5.1,3.4,1.5,0.2,Iris-5.0,3.5,1.3,0.3,Iris-,2.3,1.3,0.3,Iris-4.4,3.2,1.3,0.2,Iris-5.0,3.5,1.6,0.6,Iris-5.1,3.8,1.9,0.4,Iris-4.8,3.0,1.4,0.3,Iris-5.1,3.8,1.6,0.2,Iris-,3.2,1.4,0.2,Iris-,3.7,1.5,0.2,Iris-6.2,2.2,4.5,1.5,Iris-5.6,2.5,3.9,1.1,Iris-5.6,2.5,3.9,1.1,Iris-6.4,2.9,4.3,1.3,Iris-6.4,2.9,4.3,1.3,Iris-6.4,3.1,5.5,1.PAGE6.4,3.1,5.5,1.PAGE9,Iris-6.9,3.1,5.1,2.3,Iris-Pandas的意义Inimportimportpandasasirisdata=pd.read_csv('S1EP3_Iris.txt',header=None,encoding='utf-8')012340Iris-1Iris-2Iris-3Iris-4Iris-5Iris-6Iris-7Iris-8Iris-9Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-150rows×5Incnamescnames=['sepal_length','sepal_width','petal_length','petal_width','class'] olumns=cnames0Iris-1Iris-2Iris-3Iris-4Iris-5Iris-6Iris-7Iris-8Iris-9Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-150rows×5InIris-Iris-Iris-In0Inprintprintforxins=print'{0:<12}'.format(.upper()),"Statistics:",'{0:>5}{1:>5}{2:>5}{3:>5}'.format(s.max(),s.min(),Iris- Iris- Iris- dtype:快速Inslogsslogs=lambdaentpy=lambdax:sp.exp((slogs(x.sum())-x.map(slogs).sum())/x.sum())Iris-Iris-Iris-欢迎来到大熊猫世Pandas的重要数据类Index(行索引，行级元数据Series：pandas的长枪(数据表中的一列或一行,观测向量,一维数组数据世界中对于任意一个的全面观测，或者对于任意一组某一属性的观测，全部可以抽象为Series的概念用值构建一个由默认index和values组成InSeries1Series1=printprintprint - -dtype:float64<class'pandas.core.series.Series'>Int64Index([0,1,2,3],dtype='int64')[0.030480420.07274621-0.18660749-Series支持过滤的原理就如同Inprintprintprint dtype:当然也支持Inprintprintprint - -dtype: dtype:以及UniversalInprintprint#NumPyUniversalf_np=np.frompyfunc(lambdaprint0123dtype:0123dtype:在序列上就使用行标，而不是创建一个2列的数据表，能够轻松辨别哪里是数据，哪里是元数据InSeries2Series2=pd.Series(Series1.values,index=['norm_'+unicode(i)foriinprintprintSeries2.indexprintSeries2.values--float64<classIndex([u'norm_0',u'norm_1',u'norm_2',u'norm_3'],<class[0.030480420.07274621-0.18660749-虽然行是有顺序的，但是仍然能够通过行级的index来到数据（当然也不尽然像OrderedDict，因为行索引甚至可以重复，不推荐重复的行索引不代表不能用Inprintprint dtype:float64Inprintprint'norm_0'inprint'norm_6'in默认行索引就像行号一样InprintprintInt64Index([0,1,2,3],从Key不重复的OrderedDict或者从Dict来定义Series就不需要担心行索引重复InSeries3_DictSeries3_Dict={"Japan":"Tokyo","S.Korea":"Seoul","China":"Beijing"}Series3_pdSeries=pd.Series(Series3_Dict)printprintprint dtype:object['Beijing''Tokyo'Index([u'China',u'Japan',u'S.Korea'],想让序列按你的排序方式保存？就算有缺失值都毫无问InSeries4_IndexList=["Japan","China","Singapore","S.Korea"]Series4_pdSeriesSeries4_IndexList=["Japan","China","Singapore","S.Korea"]Series4_pdSeries=pd.Series(Series3_Dict,index=Series4_IndexList)printSeries4_pdSeriesprintSeries4_pdSeries.valuesprintSeries4_pdSeries.indexprintSeries4_pdSeries.isnull()print S.KoreaSeouldtype:['Tokyo''Beijing'nanIndex([u'Japan',u'China',u'Singapore',u'S.Korea'],dtype='object') dtype:bool dtype:bool整个序列级别的元数据信息当数据序列以及index本身有了名字，就可以更方便的进行后续的数据关联InprintprintprintInInSeries4_pdSSeries4_pdS="CapitalSeries"Series4_pdS="Nation"printSeries4_pdSeries ChinaBeijingSingaporeNaNS.KoreaSeoulName:CapitalSeries,dtype:"字典"？不是的，行index可以重复，尽管不推荐InSeries5_IndexListSeries5_IndexList=Series5=pd.Series(Series1.values,index=printprintABB-C-dtype:BB-Adtype:Series的有序集合，就像R的DataFrame一样方便仔细想想，绝大部分的数据形式都可以表现为DataFrame从NumPy二维数组、从文件或者从数据库定义：数据虽好，勿忘IndataNumPydataNumPy=np.asarray([('Japan','Tokyo',4000),('S.Korea','Seoul',1300),('China','Beijing',910DF1=pd.DataFrame(dataNumPy,columns=['nation','capital','GDP'])012等长的列数据保存在一个字典里（JSON）：很不幸，字典keyInIndataDictdataDict{'nation':['Japan','S.Korea','China'],'capital':['Tokyo','Seoul','Beijing'],'GDP':[DF2=012从另一个DataFrame定义DataFrame：啊，强迫症犯InDF21DF21=pd.DataFrame(DF2,columns=['nation','capital','GDP'])012InDF22DF22=pd.DataFrame(DF2,columns=['nation','capital','GDP'],index=[2,0,1])201从DataFrame中取出列？两种方法（与JavaScript完全一致'[]'的写法最安全。InInprintprintprint201nation,dtype:object01capital,dtype:201Name:GDP,dtype:从DataFrame中取出行？（至少）两种方法InprintprintDF22[0:1]#给出的实际是printDF22.ix[0]#通过对应Index2Name:0,dtype:像NumPy切片一样的终极招Inprintprintprint Name:2,dtype: Name:nation,dtype:听说你从AlterTable来，大熊猫笑然而动态增加列无法用"."的方式完成，只能用"[InDF22['population']DF22['population']=[1600,130,55]201Index：pandas进行数据的鬼牌（行级索引行级索引元数可以和列名进行交换，也可以进行堆叠和展开，达到Excel表效pd.Index（普通）Int64Index（数值型索引PeriodIndex（含周期的时间格式作为索引）直接定义普通索引，长得就和普通的SeriesInindex_names=['a','b','c']Series_for_Indexindex_names=['a','b','c']Series_for_Index=pd.Series(index_names)printpd.Index(index_names)printIndex([u'a',u'b',u'c'],Index([u'a',u'b',u'c'],可惜Immutable，牢Inindex_names=['a','b','c']index0index_names=['a','b','c']index0=pd.Index(index_names)printindex0.get_values()index0[2]='d'['a''b' Traceback(mostrecentcall<ipython-input-31-f34da0a8623c>in2index0=3print>4index0[2]=/Users/wangweiyang/anaconda/anaconda/lib/python2.7/site-packages/pandas/core/index.pycin titem(self,key,value) setitem(self,key,->1057 raiseTypeError("Indexesdoesnotsupportmutableoperations") getitem(self,TypeError:Indexesdoesnotsupportmutable扔进去一个含有多元组的List，就有了可惜，如果这个ListComprehension改成小括号，就不对了InInmulti1multi1=pd.Index([('Row_'+str(x+1),'Col_'+str(y+1))forxinxrange(4)foryinxrange(4)])=['index1','index2']printMultiIndex(levels=[[u'Row_1',u'Row_2',u'Row_3',u'Row_4'],[u'Col_1',u'Col_2',u'Col_3',u'labels=[[0,0,0,0,1,1,1,1,2,2,2,2,3,3,3,3],[0,1,2,3,0,1,2,0,1,2,3,0,1,2,对于Series来说，如果拥有了多重Index，数据下列代码In=Row_10123Row_24567Row_389Row_4dtype:In0123456789InIn0123456789我们来看一下非平衡数据的例子Row_1,2,3,4和Col_1,2,3,4并不是全组Inmulti2multi2=pd.Index([('Row_'+str(x+1),'Col_'+str(y+1))forxinxrange(5)foryinxrange(x)])MultiIndex(levels=[[u'Row_2',u'Row_3',u'Row_4',u'Row_5'],[u'Col_1',u'Col_2',u'Col_3',u'labels=[[0,1,1,2,2,2,3,3,3,3],[0,0,1,0,1,2,0,1,2,In=pd.Series(np.arange(10),index=Row_20Row_312Row_4345Row_56789dtype:In0123456789In0123456789DateTime标准库如此好用，你值得Indatesdates=[datetime.datetime(2015,1,1),datetime.datetime(2015,1,8),datetime.datetime(2015,1,30)]DatetimeIndex(['2015-01-01','2015-01-08','2015-01-30'],dtype='datetime64[ns]',freq=None,t如果你不仅需要时间格式统一，时间频率也要统一的Inperiodindex1periodindex1=pd.period_range('2015-01','2015-printPeriodIndex(['2015-01','2015-02','2015-03','2015-04'],dtype='int64',月级精度和日级精度如何转有的公司统一以1号代表当月，有的公司统一以最后一天代表当月，转化起来很麻烦，可以InprintprintprintPeriodIndex(['2015-01-01','2015-02-01','2015-03-01','2015-04-01'],dtype='int64',PeriodIndex(['2015-01-31','2015-02-28','2015-03-31','2015-04-30'],dtype='int64',最后的最后，我要真正把两种频率的时间精度匹配上Inperiodindex_monperiodindex_mon=pd.period_range('2015-01','2015-03',freq='M').asfreq('D',how='start')periodindex_day=pd.period_range('2015-01-01','2015-03-31',freq='D')printprintPeriodIndex(['2015-01-01','2015-02-01','2015-03-01'],dtype='int64',PeriodIndex(['2015-01-01','2015-01-02','2015-01-03','2015-01-'2015-01-05','2015-01-06','2015-01-07','2015-01-'2015-01-09','2015-01-10','2015-01-11','2015-01-'2015-01-13','2015-01-14','2015-01-15','2015-01-'2015-01-17','2015-01-18','2015-01-19','2015-01-'2015-01-21','2015-01-22','2015-01-23','2015-01-'2015-01-25','2015-01-26','2015-01-27','2015-01-'2015-01-29','2015-01-30','2015-01-31','2015-02-'2015-02-02','2015-02-03','2015-02-04','2015-02-'2015-02-06','2015-02-07','2015-02-08','2015-02-'2015-02-10','2015-02-11','2015-02-12','2015-02-'2015-02-14','2015-02-15','2015-02-16','2015-02-'2015-02-18','2015-02-19','2015-02-20','2015-02-'2015-02-22','2015-02-23','2015-02-24','2015-02-'2015-02-26','2015-02-27','2015-02-28','2015-03-'2015-03-02','2015-03-03','2015-03-04','2015-03-'2015-03-06','2015-03-07','2015-03-08','2015-03-'2015-03-10','2015-03-11','2015-03-12','2015-03-'2015-03-14','2015-03-15','2015-03-16','2015-03-'2015-03-18','2015-03-19','2015-03-20','2015-03-'2015-03-22','2015-03-23','2015-03-24','2015-03-'2015-03-'2015-03-

'2015-03-'2015-03-

'2015-03-28','2015-03-粗粒度数据Infull_tsfull_ts=pd.Series(periodindex_mon,index=periodindex_mon).reindex(periodindex_day,method='ffi2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-01-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-2015-03-Freq:D,dtype:关于索引，方便的操作有前面描述过了，索引有序，重复，但一定程度上又能通过key来，也就是说，某些集合操作都是可以支持的Inindex1index1=index2=index3=pd.Index(['B','C','A'])printindex1.append(index2)printindex1.difference(index2)printindex1.union(index2)#Supportunique-valueIndexprintprintprintindex1.insert(0,'K')#Notprintindex3.drop('A')#Supportunique-valueIndexprintprintIndex([u'A',u'B',u'B',u'C',u'C',u'C',u'D',u'E',u'E',u'F'],dtype='object')Index([u'A',u'B'],dtype='object')Index([u'C',u'C'],Index([u'A',u'B',u'B',u'C',u'C',u'D',u'E',u'E',u'F'],dtype='object')[FalseFalseFalseTrueTrue]Index([u'A',u'B',u'C',u'C'],Index([u'K',u'A',u'B',u'B',u'C',u'C'],dtype='object')Index([u'B',u'C'],dtype='object')TrueTrueFalseFalseFalse大熊猫世界来去自如：Pandas的老生常谈，从基础来看，我们仍然关心pandas对于与外部数据是如何交互read_csv与 是一对输入输出的工具，read_csv直接返回pandas.DataFrame，而to_csv只要执行命令即可写文read_fwf：操作fixedwidthfileread_excel与to_excel方便的与excel还记得刚开始的例子吗names表示要用给定的列名来作为最终的列名encoding表示数据集的字符编码，通常而言一份数据为了方便的进行文件传输都以utf-8作为标准 Inprintprintirisdata=pd.read_csv('S1EP3_Iris.txt',header=None,names=cnames,encoding='utf-8')['sepal_length','sepal_width','petal_length','petal_width','class']0Iris-1Iris-2Iris-3Iris-4Iris-5Iris-6Iris-7Iris-8Iris-9Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-150希望ws×5解全部参数的s移步(这(这里介绍一些常用的参数处理skiprows：跳过一定的行 一定的行数skipfooter：尾部固定的行数永不 内容处理sep/delimiter：分隔符很重要，常见的有逗号，空格和na_values：指定应该被当作na_valuesthousands：处值类，每分隔不统一 (1.234.567,89或1,234,567.89，此要把串转为符收尾处理 2.1.xExcel...对于着极为规整数据的Excel而言，其实是没必要一定用Excel来存，尽管Pandas也十分友好的提供了I/O接口Inirisdata.to_excel('S1EP3_irisdata.xls',index=None,encoding='utf-8')irisdata_from_excelirisdata.to_excel('S1EP3_irisdata.xls',index=None,encoding='utf-8')irisdata_from_excel=pd.read_excel('S1EP3_irisdata.xls',header=0,encoding='utf-8')0Iris-1Iris-2Iris-3Iris-4Iris-5Iris-6Iris-7Iris-8Iris-9Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-150rows×5唯一重要的参数：sheetname=k，标志着一个excel的第k个sheet页将会被取出。（从0开始JSON：网络传输中常用的一种数据key可能元数据被保存在数Injson_datajson_data=data_employee=pd.read_json(json.dumps(json_data))data_employee_ri=data_employee.reindex(columns=['name','job','sal','report'])012深入Pandas数在第一部分的基础上，数据会有种方式按记录拼接（就像UnionAll）或者关联（join）缺失值处与Excel一样灵活的数据表（在第四部分更详细介绍横向拼接：直接In012InIn012012012可以使用left_on和In012In012根据index关联，可以直接使用left_index和InIndata_employee_='index1'data_employee_='index1'012TIPS:增加how关键字，并how='inner'how='left'how='right'结合how，可以看到merge基本再现了SQL应有的功能，并保持代码IndataNumPy32dataNumPy32=np.asarray([('Japan','Tokyo',4000),('S.Korea','Seoul',1300),('China','Beijing',9DF32=pd.DataFrame(dataNumPy,columns=['nation','capital','GDP'])012InIndefdefGDP_Factorize(v):fv=np.float64(v)iffv>6000.0:returneliffv<returnreturnDF32['GDP_Level']=DF32['GDP'].map(GDP_Factorize)DF32['NATION']=DF32.nation.map(str.upper)012sort:按一列或者多列的值进行行级排sort_index:根据index里的取值进行排序，而且可以根据axis决定是重还是IndataNumPy33dataNumPy33=np.asarray([('Japan','Tokyo',4000),('S.Korea','Seoul',1300),('China','Beijing',9DF33=pd.DataFrame(dataNumPy,columns=['nation','capital','GDP'])012In102InIn012In210In012一个好用的功In023213212113InIn021211232331注意tieddata（相同值）的处理：method='average'method='min'method='max'method='first'InDF34DF34=data_for_multi2.unstack()0123456789忽略缺失Indtype:如果不想忽略缺失值的话，就需要祭出fillnaInIn In“一组”大熊猫：Pandas的groupby的功能类似SQL的groupby关键字Split，就是按照规Pandas的groupby的灵活InfromfromIPython.displayimportImage分组的具Inirisdata_groupirisdata_group=irisdata.groupby('class')<pandas.core.groupby.DataFrameGroupByobjectatInforforlevel,subsetDFinprintprintIris-sepal_lengthsepal_widthpetal_length 0.2Iris- 0.2Iris- 0.2Iris- 0.2Iris- 0.2Iris- 0.4Iris- 0.3Iris- 0.2Iris- 0.2Iris- 0.1Iris- 0.2Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-Iris-sepal_lengthsepal_widthpetal_length 1.4Iris- 1.5Iris- 1.5Iris- 1.3Iris- 1.5Iris- 1.3Iris- 1.6Iris- 1.0Iris- 1.3Iris- 1.4Iris- 1.0Iris- 1.5Iris- 1.0Iris- 1.4Iris- 1.3Iris- 1.4Iris- 1.5Iris- 1.0Iris- 1.5Iris- 1.1I