Python Read Text File Mac File Path Invalid Syntax

This tutorial covers the following topic – Python Write File/Read File. Information technology describes the syntax of the writing to a file in Python. Likewise, information technology explains how to write to a text file and provides several examples for help.

For writing to a file in Python, you would need a couple of functions such every bit Open() , Write() , and Read() . All these are congenital-in Python functions and don't require a module to import.

There are majorly ii types of files yous may have to interact with while programming. Ane is the text file that contains streams of ASCII or UNICODE (UTF-8) characters. Each line ends with a newline ("\n") char, a.k.a. EOL (End of Line).

Some other blazon of file is chosen binary that contains car-readable data. It doesn't have, so-called line as there is no line-ending. Simply the application using information technology would know about its content.

Anyways, this tutorial will strictly tell you to work with the text files but.

Python Write File Explained with Examples

Let'southward begin this tutorial by taking on the beginning telephone call required to write to a file in Python, i.e., Open() .

Open File in Python

You first have to open a file in Python for writing. Python provides the congenital-in open() function.

The open() role would return a handle to the file if it opened successfully. It takes two arguments, every bit shown below:

''' Python open file syntax '''  file_handle = open up("file_name", "access_mode")

The first argument is the name or path of the file (including file proper name). For example – sample_log.txt or /Users/john/home/sample_log.txt.

And the second parameter (optional) represents a mode to open up the file. The value of the "access_mode" defines the operation you want to perform on it. The default value is the READ only mode.

# Open a file named "sample_log.txt"  # It rests in the same directory as you are working in.  file_handle1 = open("sample_log.txt")  # Let's open the file from a given path file_handle2 = open("/Users/john/dwelling/sample_log.txt")

File Open up Modes

Information technology is optional to laissez passer the manner argument. If you lot don't fix it, then Python uses "r" as the default value for the admission style. It means that Python will open a file for read-but purpose.

However, at that place are a total of half dozen access modes available in python.

• "r" –  Information technology opens a text file for reading. It keeps the start at the start of the file. If the file is missing, then it raises an I/O mistake. It is also the default manner.
• "r+" –  It opens the file for both READ and WRITE operations. It sets the get-go at the start of the file. An I/O error occurs for a not-existent file.
• "w" –  It opens a file for writing and overwrites any existing content. The handle remains at the starting time of the data. If the file doesn't exist, so it creates one.
• "w+" –  It opens the file for both READ and WRITE operations. Residual, it works the same as the "w" manner.
• "a" –  It opens a file for writing or creates a new 1 if the file not establish. The handle moves to the end (EOF). It preserves the existing content and inserts data to the end.
• "a+" –  It opens the file for both READ and WRITE operations. Rest, it works the same every bit the "a" fashion.

Check out a few examples:

# Open a file named "sample_log.txt" in write fashion ### # It rests in the aforementioned directory as yous are working in. file_handle1 = open up("sample_log.txt", "w")  # Open the file from a given path in append mode file_handle2 = open up("/Users/john/dwelling house/sample_log.txt", "a")

Write File in Python

Python provides two functions to write into a text file: Write() and Writelines() .

1. write() – Let's offset utilise write() for writing to a file in Python. This function puts the given text in a single line.

''' Python write() part '''  file_handle.write("some text")

But, first, open up any IDE and create a file named "sample_log.txt" for our test. Don't make whatever other changes to information technology.

Please note – If you endeavour to open a file for reading and it doesn't exist, then Python will throw the FileNotFoundError exception.

To edit this file from your Python program, nosotros've given the post-obit code:

# A simple instance - Python write file ### file_handle = open("sample_log.txt","w")   file_handle.write("Hullo Everyone!")  file_handle.write("It is my commencement try to write to a file in Python.")  file_handle.write("I'll get-go open the file and then write.")  file_handle.write("Finally, I'll shut it.")   file_handle.close()

We've opened the file in "w" mode, which means to overwrite annihilation written previously. And then, after you open up it and see its content, you'll find the new text in iv different lines.

2. writelines() – The writelines() function takes a listing of strings as the input and inserts each of them as a dissever line in one get. You tin can check its syntax below:

''' Python writelines() function '''  file_handle.writelines([str1, str2, str3, ...])

Append File in Python

You also need to know how to append the new text to an existing file. At that place are two modes available for this purpose: a and a+.

Whenever y'all open a file using i of these modes, the file first is prepare to the EOF. And then, you can write the new content or text side by side to the existing content.

Let'southward understand it with a few lines of code:

We'll first open a file in "a" manner. If you run this example the first time, and so information technology creates the file.

# Python Suspend File in "a" mode Example ### fh = open("test_append_a.txt", "a") fh.write("Insert Outset Line\due north") fh.write("Suspend Next Line\n")

So far, two lines have been added to the file. The 2d write operation indicates a successful append.

At present, you'll see the difference between the "a" and "a+" modes. Permit's try a read operation and see what happens.

fh.read() # io.UnsupportedOperation: not readable

The above line of lawmaking would fail equally the "a" way doesn't let READ. So, close it, open, and so do a read operation.

fh.close() # Shut the file fh = open up("test_append_a.txt") # Open in the default read mode print(fh.read()) # Now, read and print the unabridged file fh.close()

The output is something like:

Insert Offset Line Suspend Next Line

Permit'south now effort appending using the "a+" mode. Check out the below code:

# Python Append File in "a+" mode Instance ### fh = open("test_append_aplus.txt", "a+") fh.write("Insert Beginning Line\due north") fh.write("Append Next Line\n") fh.seek(0) # Set up offset position to the start print(fh.read()) # READ is sucess in a+ mode  ## Output  # Insert First Line  # Append Next Line fh.write("Append Another Line\north") # WRITE another line to the text file fh.seek(0) # Set the offset for reading impress(fh.read()) # Do the READ performance again  ## Output  # Insert First Line  # Suspend Next Line  # Suspend Another Line

Read File in Python

For reading a text file, Python bundles the following three functions: read() , readline() , and readlines()

i. read() – It reads the given no. of bytes (N) as a string. If no value is given, then it reads the file till the EOF.

''' Python read() function ''' #Syntax file_handle.read([Northward])

two. readline() – It reads the specified no. of bytes (N) every bit a string from a unmarried line in the file. Information technology restricts to 1 line per phone call even if N is more than the bytes bachelor in one line.

''' Python readline() function ''' #Syntax file_handle.readline([North])

3. readlines() – Information technology reads every line presents in the text file and returns them as a list of strings.

''' Python readlines() part ''' #Syntax file_handle.readlines()

Information technology is so easy to use the Python read file functions that y'all tin cheque yourself. Merely type the following code in your IDE or the default Python IDE, i.e., IDLE.

# Python Read File Example ### fh = open("sample_log.txt") # No demand to specify the fashion as READ is the default style print(fh.read()) # Await the whole file to get printed hither fh.seek(0) # Reset the file offset to the beginning of the file print(fh.readline()) # Impress just the first line from the file fh.seek(0) # Reset the first again print(fh.readlines()) # Print the list of lines fh.close() # Close the file handle

Delight note that the Python seek() office is needed to alter the position of file kickoff. It decides the point to read or write in the file. Whenever you lot practise a read/write operation, it moves along.

Close File in Python

File handling in Python starts with opening a file and ends with endmost information technology. It ways that you lot must close a file later you are finished doing the file operations.

Closing a file is a cleanup activity, which ways to free upward the system resources. It is besides essential because you can simply open a limited number of file handles.

Likewise, delight note that any effort to access the file afterward closing would throw an I/O error. Yous may accept already seen us using it in our previous examples in this post.

With Statement in Python

If you want a cleaner and elegant way to write to a file in Python, then try using the WITH statement. It does the automatic clean upwardly of the arrangement resources like file handles.

Likewise, it provides out of the box exception handling (Python try-except) while y'all are working with the files. Check out the following example to see how with statement works.

# Write File in Python using WITH statement ## # Sample code(i) Write to a text file fh = open("sample_log.txt", "w")  try:     fh.write("I love Python Programming!")  finally:     fh.close()  # Sample code(2) Write using with statement  with open up("sample_log.txt", "w") as fh:     fh.write("I love Python even more than!!")

Working sample lawmaking

Beneath is a full-fledged example that demonstrates the usage of the following functions:

• Python Write file using write() & writelines()
• Python Read file operations using read(), readline(), and readlines()

# Python Write File/ Read File Example ### print("### Python Write File/ Read File Instance ###\n") file_handle = open("sample_log.txt", "west")  list_of_strings = ["Python programming \due north","Web development \due north","Agile Scrum \n"]   # Write a newline char at each line in the file file_handle.write("Welcome! \n")  file_handle.writelines(list_of_strings)  file_handle.close()  # Open the text file for reading file_handle = open("sample_log.txt", "r+")   # Read the unabridged text file and display its content impress("1) Demonstrate Python read() part") out = file_handle.read() print("\north>>>Python read() file output:\n{}".format(out))  # Now, set up the file first to the outset file_handle.seek(False)  # Read the first line from the text file using readline() impress("ii) Demonstrate Python readline() function") out = file_handle.readline()  print("\northward>>>Python readline() file output:\n\tLine#ane{}".format(out))  # Once again, position the file kickoff to naught file_handle.seek(False)   # Read the unabridged text file using readlines() impress("3) Demonstrate Python readlines() part") out = file_handle.readlines() file_handle.shut() impress("\north>>>Python readlines() file output:") for i, line in enumerate(out):   impress("\tLine#{} {}".format(i+1, line))

This Python program generates the following output:

Attempt the Quiz

We've now come to the closure of this Read/Write File in Python tutorial. If y'all have read information technology from the showtime to end, so file treatment would exist on your tips. However, we recommend the following quizzes to attempt.

These are quick questionnaires to test how much noesis have you lot retained afterward reading the above stuff.

• Python File Treatment Quiz – Part1
• Python File Handling Quiz – Part2

Too, you must use these concepts in your projects or tin can as well write some easily-on lawmaking to solve real-time problems. Information technology'll certainly help you grasp faster and remember better.

By the style, if y'all wish to learn Python from scratch to depth, then practise read our step by step Python tutorial .

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