search
HomeBackend DevelopmentPython TutorialPython implements the function of merging two files

Python implements the function of merging two files

Apr 02, 2018 pm 04:03 PM
pythonmergedocument

This article mainly introduces the function of merging two files in Python in detail. It is a simple file merging program that has certain reference value. Interested friends can refer to it.

This article will It will analyze a file merging program and point out the issues that need to be paid attention to during the file merging process.

The following is an example of the files that need to be merged:


## Analysis idea:


To merge two files, the file must first be read into the memory and become a list. Then split the list and store the data separately according to categories, that is, name, phone number, and email address. By traversing List 1, compare it with List 2 in turn. If there are overlapping people in the two, directly use .join([ ]) to merge the names, phone numbers and emails into one row and save them in another list variable. If the two do not overlap, it means that they are only in list 1, so the email information of this person is replaced with str (‘—–’).


After this traversal, all the people in List 1 and the duplicate people in List 2 and List 1 have been re-integrated into the new list variable. Next, you need to add the unique people in list 2 to the new list variable. The method is to traverse list 2 and take out the people who do not overlap with list 1 and save them.


Finally, write the data in the new list variable to the new file and close all files.


The flow chart is as follows:

The code is as follows:


"""
Created on Fri Aug 4 12:59:36 2017

@author: 13323
"""
# This program can combine two or more files into one file.
def main():
 #firstly open the files
 data1 = open("test_3.txt","rb")
 data2 = open("test_4.txt","rb")

 # read the data in file into list
 data1.readline() #only read one line, skip the first line
 data2.readline() #only read one line, skip the first line
 file1 = data1.readlines() #read all variable into list file1 
 file2 = data2.readlines() #read all variable into list file2
 #print(file1)

 #define particular list to store variable
 file1_name = []
 file1_tel = []
 file2_name = []
 file2_email = []
 #file3 = []

 #split file1 into two part
 for line in file1:
  element = line.split() #line.split(); devide by ' '
  file1_name.append(str(element[0].decode('gbk')))
  file1_tel.append(str(element[1].decode('gbk')))

 #split file2 into two part
 for line in file2:
  element = line.split()
  file2_name.append(str(element[0].decode('gbk')))
  file2_email.append(str(element[1].decode('gbk')))

 # pick up the name in the file1 same as the name in the file2 and combine 
 file3 = []
 for i in range(len(file1_name)):
  s = ''
  if file1_name[i] in file2_name:
   j = file2_name.index(file1_name[i])
   s = '\t'.join([file1_name[i],file1_tel[i],file2_email[j]])
   s += '\n'
  else:
   s = '\t'.join([file1_name[i],file1_tel[i],str("----")])
   s += '\n'
  file3.append(s)

 #pick up the name in the file1 doesn't same as the name in the file2 
 for i in range(len(file2_name)):
  s = ''
  if file2_name[i] not in file1_name:
   s = '\t'.join([file2_name[i],str('----'),file2_email[i]])
   s += '\n'
  file3.append(s)

 #write the data into file3 
 data3 = open("test_5.txt","w")
 data3.writelines(file3)

 #close the file
 data1.close()
 data2.close()
 data3.close()

main()


Key points:

Encoding and decoding

List merging and dismantling

Related recommendations:

Two pythons implement switching function

Python method to implement management site


The above is the detailed content of Python implements the function of merging two files. For more information, please follow other related articles on the PHP Chinese website!

Statement
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn
What are the alternatives to concatenate two lists in Python?What are the alternatives to concatenate two lists in Python?May 09, 2025 am 12:16 AM

There are many methods to connect two lists in Python: 1. Use operators, which are simple but inefficient in large lists; 2. Use extend method, which is efficient but will modify the original list; 3. Use the = operator, which is both efficient and readable; 4. Use itertools.chain function, which is memory efficient but requires additional import; 5. Use list parsing, which is elegant but may be too complex. The selection method should be based on the code context and requirements.

Python: Efficient Ways to Merge Two ListsPython: Efficient Ways to Merge Two ListsMay 09, 2025 am 12:15 AM

There are many ways to merge Python lists: 1. Use operators, which are simple but not memory efficient for large lists; 2. Use extend method, which is efficient but will modify the original list; 3. Use itertools.chain, which is suitable for large data sets; 4. Use * operator, merge small to medium-sized lists in one line of code; 5. Use numpy.concatenate, which is suitable for large data sets and scenarios with high performance requirements; 6. Use append method, which is suitable for small lists but is inefficient. When selecting a method, you need to consider the list size and application scenarios.

Compiled vs Interpreted Languages: pros and consCompiled vs Interpreted Languages: pros and consMay 09, 2025 am 12:06 AM

Compiledlanguagesofferspeedandsecurity,whileinterpretedlanguagesprovideeaseofuseandportability.1)CompiledlanguageslikeC arefasterandsecurebuthavelongerdevelopmentcyclesandplatformdependency.2)InterpretedlanguageslikePythonareeasiertouseandmoreportab

Python: For and While Loops, the most complete guidePython: For and While Loops, the most complete guideMay 09, 2025 am 12:05 AM

In Python, a for loop is used to traverse iterable objects, and a while loop is used to perform operations repeatedly when the condition is satisfied. 1) For loop example: traverse the list and print the elements. 2) While loop example: guess the number game until you guess it right. Mastering cycle principles and optimization techniques can improve code efficiency and reliability.

Python concatenate lists into a stringPython concatenate lists into a stringMay 09, 2025 am 12:02 AM

To concatenate a list into a string, using the join() method in Python is the best choice. 1) Use the join() method to concatenate the list elements into a string, such as ''.join(my_list). 2) For a list containing numbers, convert map(str, numbers) into a string before concatenating. 3) You can use generator expressions for complex formatting, such as ','.join(f'({fruit})'forfruitinfruits). 4) When processing mixed data types, use map(str, mixed_list) to ensure that all elements can be converted into strings. 5) For large lists, use ''.join(large_li

Python's Hybrid Approach: Compilation and Interpretation CombinedPython's Hybrid Approach: Compilation and Interpretation CombinedMay 08, 2025 am 12:16 AM

Pythonusesahybridapproach,combiningcompilationtobytecodeandinterpretation.1)Codeiscompiledtoplatform-independentbytecode.2)BytecodeisinterpretedbythePythonVirtualMachine,enhancingefficiencyandportability.

Learn the Differences Between Python's 'for' and 'while' LoopsLearn the Differences Between Python's 'for' and 'while' LoopsMay 08, 2025 am 12:11 AM

ThekeydifferencesbetweenPython's"for"and"while"loopsare:1)"For"loopsareidealforiteratingoversequencesorknowniterations,while2)"while"loopsarebetterforcontinuinguntilaconditionismetwithoutpredefinediterations.Un

Python concatenate lists with duplicatesPython concatenate lists with duplicatesMay 08, 2025 am 12:09 AM

In Python, you can connect lists and manage duplicate elements through a variety of methods: 1) Use operators or extend() to retain all duplicate elements; 2) Convert to sets and then return to lists to remove all duplicate elements, but the original order will be lost; 3) Use loops or list comprehensions to combine sets to remove duplicate elements and maintain the original order.

See all articles

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

Video Face Swap

Video Face Swap

Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Tools

SecLists

SecLists

SecLists is the ultimate security tester's companion. It is a collection of various types of lists that are frequently used during security assessments, all in one place. SecLists helps make security testing more efficient and productive by conveniently providing all the lists a security tester might need. List types include usernames, passwords, URLs, fuzzing payloads, sensitive data patterns, web shells, and more. The tester can simply pull this repository onto a new test machine and he will have access to every type of list he needs.

DVWA

DVWA

Damn Vulnerable Web App (DVWA) is a PHP/MySQL web application that is very vulnerable. Its main goals are to be an aid for security professionals to test their skills and tools in a legal environment, to help web developers better understand the process of securing web applications, and to help teachers/students teach/learn in a classroom environment Web application security. The goal of DVWA is to practice some of the most common web vulnerabilities through a simple and straightforward interface, with varying degrees of difficulty. Please note that this software

SublimeText3 Mac version

SublimeText3 Mac version

God-level code editing software (SublimeText3)

SublimeText3 English version

SublimeText3 English version

Recommended: Win version, supports code prompts!

SublimeText3 Linux new version

SublimeText3 Linux new version

SublimeText3 Linux latest version