尝试对2个pandas数据框进行排序，然后从一个复制到另一个

Question

I have two csv files I want to manipulate and then combine into one file. I first converted them to pandas. One pandas dataframe looks like this:

      Number  Quiz
0  111111145     0
1  111111108     1
2  111111123     1
3  111111114     0
4  111111132     0

the other like this:

Last Name First Name       Number   Quiz
0  Student1      Student1  111111123   
1  Student2      Student2  111111114   
2  Student3      Student3  111111132   
3  Student4      Student4  111111145   
4  Student5      Student5  111111108   

I want to end up with something like this:

Last Name First Name       Number       Quiz
    0  Student1      Student1  111111108  1   
    1  Student2      Student2  111111114  0 
    2  Student3      Student3  111111123  1
    3  Student4      Student4  111111132  0 
    4  Student5      Student5  111111145  0

but when I run my code I end up getting:

Last Name First Name       Number       Quiz
    0  Student1      Student1  111111108  0   
    1  Student2      Student2  111111114  1 
    2  Student3      Student3  111111123  0
    3  Student4      Student4  111111132  1 
    4  Student5      Student5  111111145  0

And I am not sure why. My code is as follows:

import argparse
import sys, re
import numpy as np
import smtplib
from random import randint
import csv
import math
import pandas as pd

parser = argparse.ArgumentParser()
parser.add_argument('-cname', '--c', help = 'column name to copy')
parser.add_argument('-source', '--s', help = 'source file with the column to copy')
parser.add_argument('-target', '--t', help = 'the target file with the names and UINS')
parser.add_argument('-out', '--f', help = 'output file with column copied')

if len(sys.argv)==1:
    parser.print_help()
    sys.exit(1)
args = parser.parse_args()



sourceFile = pd.read_csv(args.s)
targetFile = pd.read_csv(args.t)
print sourceFile
print targetFile
del targetFile[args.c]
sourceFile.sort_values('UIN', ascending = True, inplace = True)
targetFile.sort_values('UIN', ascending = True, inplace = True)
print sourceFile
print targetFile
targetFile[args.c]= sourceFile[args.c]
targetFile.to_csv(args.f, index = False)
print targetFile

Answer 1

you should use a merge to get your output :

merged = df1.merge(df2, on="Number")

Should work, but you might have a problem of duplicated "Quiz" column if it appears in df1.

you can use the following to remove this problem (removes the quiz column from your first dataframe before it computes:

merged = df1[df1.columns[:-1]].merge(df2, on="Number")

Answer 2

I changed it just a little and got it to work. I used

result = pd.merge(targetFile, sourceFile, on = 'number')