Thursday, 22 February 2018

Python Read Write File,Binary Read Write File - Day 11(2 days later)

  • *Read Write File

  •   
    # #this shows how to open and read contents from the file
    # samplefilevar = open("D:/WORK/2018\February/20-02-2018-Tuesday/pythonsamplereadfile.txt",'r')
    # for linevar in samplefilevar:
    #     print (linevar)
    # samplefilevar.close()
    #
    # print("===="*20)
    # #print only the lines containing the specific word
    # samplefilevar = open("D:/WORK/2018\February/20-02-2018-Tuesday/pythonsamplereadfile.txt",'r')
    # for linevar in samplefilevar:
    #     if "file" in linevar.lower():
    #         print (linevar,end = '')
    # samplefilevar.close()
    # print("===="*20)
    # #using with keyword will automatically close the file,we dont need to
    # #use the separate close statement
    #
    # with open("D:/WORK/2018\February/20-02-2018-Tuesday/pythonsamplereadfile.txt",'r')as var2:
    #     for line in var2:
    #         #end = '' is used to avoid using the extra empty line
    #         print(line,end='')
    
    # with open("D:/WORK/2018\February/20-02-2018-Tuesday/pythonsamplereadfile.txt",'r')as var2:
    #     line =var2.readline()
    #     print(line)
    # with open("D:/WORK/2018\February/20-02-2018-Tuesday/pythonsamplereadfile.txt",'r')as var2:
    #     #readlines will read all lines and piut it into list,so it is better to use readline,
    #     #since the readlines will read the entire file in memory,where as readline will
    #     #go row by row
    #     lines =var2.readlines()
    #     print(lines)
    #
    # for line1 in lines:
    #     print(line1,end='')
    
    #write contents to a file
    # cities = ["Delhi","Bombay","Chennai"]
    #
    # with open("D:/WORK/2018\February/20-02-2018-Tuesday/pythonsamplewritefile1.txt",'w')as var2:
    #     for city in cities:
    #         print(city,file=var2)
    #
    # with open("D:/WORK/2018\February/20-02-2018-Tuesday/pythonsamplewritefile1.txt",'r')as var3:
    #     cities = var3.readlines()
    # print(cities)
    #
    # #strip functions strips the character that is present at the end or beginning 
    #,but not the middle
    # for city in cities:
    #     print(city)
    #     print(city.strip("\n"))
    #
    # cityvar1 = []
    # with open("D:/WORK/2018\February/20-02-2018-Tuesday/pythonsamplewritefile1.txt",'r')as var3:
    #     cities = var3.readlines()
    #     for city in cities:
    #         cityvar1.append(city)
    #
    # print(cityvar1)
    #
    # cityvar2 = []
    # with open("D:/WORK/2018\February/20-02-2018-Tuesday/pythonsamplewritefile1.txt",'r')as var3:
    #     cities = var3.readlines()
    #     for city in cities:
    #         cityvar2.append(city.strip("\n"))
    #
    # print(cityvar2)
    #
    # strvar1 = "testing"
    # print(strvar1.strip("s"))
    # print(strvar1.strip("g"))
    # #below will remove t at the beginning not the st at the middle
    # print(strvar1.strip("st"))
    
    
    #tuples to file
    # albumtuplevar2 = "muthu","rahman",2000,(1,"oruvan oruvan"),(2,"kuluvall"),(3,"vidukathaya")
    # print(albumtuplevar2)
    # title,composer,year,track1,track2,track3 =albumtuplevar2
    # print(title)
    # print(composer)
    # print(year)
    # print(track1)
    # print(track2)
    # print(track3)
    #
    # with open("D:/WORK/2018\February/20-02-2018-Tuesday/pythonsamplewritefile2.txt",'w')as var2:
    #     print(albumtuplevar2,file=var2)
    
    with open("D:/WORK/2018\February/20-02-2018-Tuesday/pythonsamplewritefile2.txt",'r')as var3:
        var4 = var3.readlines()
    print(var4)
    print(var4)
    ######################################################################
    #appending the tables to the existing file
    #if we use the mode 'a',it will append it ,if we use the mode 'w',it will overwrite the file
    #our challenge is to print like
    #1 times 2 is 2
    #2 times 2 is 4
    #....
    #likewise till 13 table
    
    with open("D:/WORK/2018/February/20-02-2018-Tuesday/pythonwritefile3.txt",'w')as tables:
        for i in range(1,1000):
            for j in range(1,1000):
                print("{1} times {0} is {2}".format(i,j,i*j),file=tables)
            print("=="*20,file=tables)
    
    #######################################################################
    #We can use pickle ,instead of converting the binaty manually and reconverting
    #while reading
    
    import pickle
    
    imedla = ('More Mayhem',
              'Imelda May',
              '2011',
              ((1,'Pulling the rug'),
               (2,'Psycho'),
               (3,'Mayhem'),
               (4,'Kentish Town Waltz')))
    
    # with open("D:/WORK/2018/February/22-02-2018-Thursday/pythonwritefilebinary.pickle","wb") 
    as pickle_file:
    #     pickle.dump(imedla,pickle_file)
    
    with open("D:/WORK/2018/February/22-02-2018-Thursday/pythonwritefilebinary.pickle","rb")
    as imelda_pickled:
        imelda2 = pickle.load(imelda_pickled)
    
    print(imelda_pickled)
    print(imelda2)
    album,artist,year,tracklist = imelda2
    print (album)
    print (artist)
    print (year)
    for track in tracklist:
        trackno,tracktile = track
        print("{0} : {1}".format(trackno,tracktile))
    #########################################################################################
    #storing multiple objects in the binary file and retrieving it in the same order
    import pickle
    
    imedla = ('More Mayhem',
              'Imelda May',
              '2011',
              ((1,'Pulling the rug'),
               (2,'Psycho'),
               (3,'Mayhem'),
               (4,'Kentish Town Waltz')))
    
    even = list(range(0,10,2))
    odd = list(range(1,10,2))
    
    with open("D:/WORK/2018/February/22-02-2018-Thursday/pythonwritefilebinary2.pickle","wb") 
    as pickle_file:
        pickle.dump(imedla,pickle_file,protocol=0)
        pickle.dump(even,pickle_file,protocol=0)
        pickle.dump(odd,pickle_file,protocol=0)
        pickle.dump(12345,pickle_file,protocol=0)
    #to read the above objects we need to read it in the same order ie..tuples,list,variable
    
    with open("D:/WORK/2018/February/22-02-2018-Thursday/pythonwritefilebinary2.pickle","rb")
    as imelda_pickled:
        imelda2 = pickle.load(imelda_pickled)
        even_list = pickle.load(imelda_pickled)
        odd_list = pickle.load(imelda_pickled)
        x = pickle.load(imelda_pickled)
    
    print(imelda_pickled)
    print(imelda2)
    album,artist,year,tracklist = imelda2
    print (album)
    print (artist)
    print (year)
    for track in tracklist:
        trackno,tracktile = track
        print("{0} : {1}".format(trackno,tracktile))
    
    print("="*40)
    
    for i in even_list:
        print(i)
    print("="*40)
    for i in odd_list:
        print(i)
    print("="*40)
    print(x)
    ###################################################################################
    
     
    

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