Python - Read CSV Columns Into List - GeeksforGeeks

In this method we will import the csv library and open the file in reading mode, then we will use the DictReader() function to read the data of ... 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ImproveArticle SaveArticle LikeArticle DifficultyLevel: MediumLastUpdated: 17Sep,2021ReadDiscussViewDiscussion ImproveArticle SaveArticle LikeArticle CSVfilestorestabulardata(numbersandtext)inplaintext.Eachlineofthefileisadatarecord.Eachrecordconsistsofoneormorefields,separatedbycommas.Theuseofthecommaasafieldseparatoristhesourceofthenameforthisfileformat.Inthisarticle,wewillreaddatafromaCSVfileintoalist.Wewillusethepanda’slibrarytoreadthedataintoalist. FileUsed:file.Method1:UsingPandasHere,wehavetheread_csv()functionwhichhelpstoreadtheCSVfilebysimplycreatingitsobject.Thecolumnnamecanbewritteninsidethisobjecttoaccessaparticularcolumn,thesameaswedoinaccessingtheelementsofthearray.Pandaslibraryhasafunctionnamedastolist()thatconvertsthedataintoalistthatcanbeusedasperourrequirement.So,wewillusethistoconvertthecolumndataintoalist.Finally,wewillprintthelist.Approach:Importthemodule.ReaddatafromCSVfile.Convertitintothelist.Printthelist.Belowistheimplementation:Python3#importingmodulefrompandasimport* #readingCSVfiledata=read_csv("company_sales_data.csv") #convertingcolumndatatolistmonth=data['month_number'].tolist()fc=data['facecream'].tolist()fw=data['facewash'].tolist()tp=data['toothpaste'].tolist()sh=data['shampoo'].tolist() #printinglistdataprint('Facecream:',fc)print('Facewash:',fw)print('Toothpaste:',tp)print('Shampoo:',sh)Output:Method2:UsingcsvmoduleInthismethodwewillimportthecsvlibraryandopenthefileinreadingmode,thenwewillusetheDictReader()functiontoreadthedataoftheCSVfile.Thisfunctionislikearegularreader,butitmapstheinformationtoadictionarywhosekeysaregivenbythecolumnnamesandallthevaluesaskeys.Wewillcreateemptylistssothatwecanstorethevaluesinit.Finally,weaccessthekeyvaluesandappendthemintotheemptylistsandprintthatlist.Python3#importingthemoduleimportcsv #openthefileinreadmodefilename=open('company_sales_data.csv','r') #creatingdictreaderobjectfile=csv.DictReader(filename) #creatingemptylistsmonth=[]totalprofit=[]totalunit=[] #iteratingovereachrowandappend#valuestoemptylistforcolinfile:    month.append(col['month_number'])    totalprofit.append(col['moisturizer'])    totalunit.append(col['total_units']) #printinglistsprint('Month:',month)print('Moisturizer:',totalprofit)print('TotalUnits:',totalunit)Output:MyPersonalNotes 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