Eoferror python как исправить

Basically, I have to check whether a particular pattern appear in a line or not. If yes, I have to print that line otherwise not. So here is my code:

p = input()
 while 1:
   line = input()
   a=line.find(p)
   if a!=-1:
     print(line)
   if line=='':
     break

This code seems to be good and is being accepted as the correct answer. But there’s a catch. I’m getting a run time error EOFError: EOF when reading a line which is being overlooked by the code testing website.

I have three questions:
1) Why it is being overlooked?
2) How to remove it?
3) Is there a better way to solve the problem?

asked Mar 19, 2017 at 20:05

Nothing is overlooked. As per the documentation input raises an EOFError when it hits an end-of-file condition. Essentially, input lets you know we are done here there is nothing more to read. You should await for this exception and when you get it just return from your function or terminate the program.

def process_input():
    p = input()
    while True:
        try:
            line = input()
        except EOFError:
            return
        a = line.find(p)             
        if a != -1:
            print(line)
        if line=='':
            return

answered Mar 19, 2017 at 20:11

VS CODE FIX:

I was getting the same error using VS Code and this worked for me. I had modified the «console» line in my launch.json file to be this:

"console": "internalConsole"

I did this hoping to keep the path from printing every time I (F5) ran my program. This modification however causes it to run in the debug console which apparently doesn’t like the input function.

I’ve since changed it back to:

"console": "integratedTerminal"

And at the start of my program I just clear the terminal screen using this code (I’m in windows):

#windows command to clear screen
import os
os.system('cls')

Now when I (F5) run my program in VScode it executes in the built in terminal, clears the path garbage that gets displayed first and works like you would expect with no exceptions. My guess is that the code testing website you are using is running in some kind of debug console similar to what was happening in VSCode because your code works fine on repl.it (https://repl.it/languages/python3). There is nothing wrong with your code and there is nothing normal or expected about this EOF error.

answered Nov 27, 2020 at 6:00

Nothing is overlooked. As per the documentation input raises an EOFError when it hits an end-of-file condition. Essentially, input lets you know we are done here there is nothing more to read. You should await for this exception and when you get it just return from your function or terminate the program.def process_input(): p = input() while True: try: line = input() except EOFError: return a = line.find(p) if a != -1: print(line) if line=='': return

answered 51 mins ago

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You can use try-except block in your code using EOFError.

answered Feb 23, 2020 at 15:29

Источник

So as we can see in the pictures above, despite having produced the expected output, our test case fails due to a runtime error EOFError i.e., End of File Error. Let’s understand what is EOF and how to tackle it.

What is EOFError

In Python, an EOFError is an exception that gets raised when functions such as input() or raw_input() in case of python2 return end-of-file (EOF) without reading any input.

When can we expect EOFError

We can expect EOF in few cases which have to deal with input() / raw_input() such as:

Interrupt code in execution using ctrl+d when an input statement is being executed as shown below
Another possible case to encounter EOF is, when we want to take some number of inputs from user i.e., we do not know the exact number of inputs; hence we run an infinite loop for accepting inputs as below, and get a Traceback Error at the very last iteration of our infinite loop because user does not give any input at that iteration

n=int(input())
if(n>=1 and n<=10**5):
    phone_book={}
    for i in range(n):
        feed=input()
        phone_book[feed.split()[0]]=feed.split()[1]
    while True:
        name=input()
        if name in phone_book.keys():
            print(name,end="")
            print("=",end="")
            print(phone_book[name])
        else:
            print("Not found")

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The code above gives EOFError because the input statement inside while loop raises an exception at last iteration

Do not worry if you don’t understand the code or don’t get context of the code, its just a solution of one of the problem statements on HackerRank 30 days of code challenge which you might want to check
The important part here is, that I used an infinite while loop to accept input which gave me a runtime error.

How to tackle EOFError

We can catch EOFError as any other error, by using try-except blocks as shown below :

try:
    input("Please enter something")
except:
    print("EOF")

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You might want to do something else instead of just printing «EOF» on the console such as:

n=int(input())
if(n>=1 and n<=10**5):
    phone_book={}
    for i in range(n):
        feed=input()
        phone_book[feed.split()[0]]=feed.split()[1]
    while True:
        try:
            name=input()
        except EOFError:
            break
        if name in phone_book.keys():
            print(name,end="")
            print("=",end="")
            print(phone_book[name])
        else:
            print("Not found")

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In the code above, python exits out of the loop if it encounters EOFError and we pass our test case, the problem due to which this discussion began…

Hope this is helpful
If you know any other cases where we can expect EOFError, you might consider commenting them below.

Источник

Introduction to Python EOFError

EOFError in python is one of the exceptions handling errors, and it is raised in scenarios such as interruption of the input() function in both python version 2.7 and python version 3.6 and other versions after version 3.6 or when the input() function reaches the unexpected end of the file in python version 2.7, that is the functions do not read any date before the end of input is encountered. And the methods such as the read() method must return a string that is empty when the end of the file is encountered, and this EOFError in python is inherited from the Exception class, which in turn is inherited from BaseException class.

Syntax:

EOFError: EOF when reading a line

Working of EOFError in Python

Below is the working of EOFError:

1. BaseException class is the base class of the Exception class which in turn inherits the EOFError class.

2. EOFError is not an error technically, but it is an exception. When the in-built functions such as the input() function or read() function return a string that is empty without reading any data, then the EOFError exception is raised.

3. This exception is raised when our program is trying to obtain something and do modifications to it, but when it fails to read any data and returns a string that is empty, the EOFError exception is raised.

Examples

Below is the example of Python EOFError:

Example #1

Python program to demonstrate EOFError with an error message in the program.

Code:

#EOFError program
#try and except blocks are used to catch the exception
try:
    	while True:
       		 #input is assigned to a string variable check
        		check = raw_input('The input provided by the user is being read which is:')
        		#the data assigned to the string variable is read
        		print 'READ:', check
#EOFError exception is caught and the appropriate message is displayed
except EOFError as x:
   	 print x

Output:

Explanation: In the above program, try and except blocks are used to catch the exception. A while block is used within a try block, which is evaluated to true, and as long as the condition is true, the data provided by the user is read, and it is displayed using a print statement, and if the data cannot be read with an empty string being returned, then the except block raises an exception with the message which is shown in the output.

Example #2

Python program to demonstrate EOFError with an error message in the program.

Code:

#EOFError program
#try and except blocks are used to catch the exception
try:
    	while True:
       			 #input is assigned to a string variable check
       			 check = raw_input('The input provided by the user is being read which is:')
        			#the data assigned to the string variable is read
        		 print 'Hello', check
#EOFError exception is caught and the appropriate message is displayed
except EOFError as x:
    	print x

Output:

Explanation: In the above program, try and except blocks are used to catch the exception. A while block is used within a try block, which is evaluated to true, and as long as the condition is true, the data provided by the user is read and it is displayed using a print statement, and if the data cannot be read with an empty string being returned, then the except block raises an exception with the message which is shown in the output.

Steps to Avoid EOFError in Python

If End of file Error or EOFError happens without reading any data using the input() function, an EOFError exception will be raised. In order to avoid this exception being raised, we can try the following options which are:

Before sending the End of File exception, try to input something like CTRL + Z or CTRL + D or an empty string which the below example can demonstrate:

Code:

#try and except blocks are used to catch the exception
try:
    	data = raw_input ("Do you want to continue?: ")
except EOFError:
    	print ("Error: No input or End Of File is reached!")
    	data = ""
    	print data

Output:

Explanation: In the above program, try and except blocks are used to avoid the EOFError exception by using an empty string that will not print the End Of File error message and rather print the custom message provided by is which is shown in the program and the same is printed in the output as well. The output of the program is shown in the snapshot above.

If the EOFError exception must be processed, try and catch block can be used.

Conclusion

In this tutorial, we understand the concept of EOFError in Python through definition, the syntax of EOFError in Python, working of EOFError in Python through programming examples and their outputs, and the steps to avoid EOFError in Python.

Why Does an Eoferror: Ran Out of Input Error Occur?

The eoferror ran out of input error occurs mainly because a program calls out an empty file. Some other causes include:

The file is empty.
Using unnecessary functions in the program.
Overwrite a pickle file.
Using an unknown filename.
Using an incorrect syntax: df=pickle.load(open(‘df.p’,’rb’))

– The File Is Empty

When a file is empty and has no input details in it, the program error occurs when that file is called out. It is also known as a pickle.load eoferror error.

Given below are a quick program and its output that explains the cause of the error.

Program:

Open(target, ‘c’).close()

scores = {};

with open(target, “rb”) as file:

unpickler = pickle.Unpickler(file);

scores = unpickler.load();

if not isinstance(scores, dict):

scores = {};

Output:

Traceback (most recent call last):

File “G:pythonpenduuser_test.py”, line 3, in :

save_user_points(“Magixs”, 31);

File “G:pythonpenduuser.py”, line 22, in save_user_points:

scores = unpickler.load();

EOFError: Ran out of input

Now, the reason why this error occurred was that the program called an empty file, and no other command was given.

– Using Unnecessary Functions in the Program

Sometimes, using an unnecessary function in the program can lead to undefined behavior in the output or errors such as EOFError: Ran out of the input.

Therefore, avoid using functions that are not required. Here’s the same example from above for avoiding confusion:

Open(target, ‘c’).close()

scores = {};

with open(target, “rb”) as file:

unpickler = pickle.Unpickler(file);

scores = unpickler.load();

if not isinstance(scores, dict):

scores = {};

– Overwrite a Pickle File

Sometimes, an empty pickle file can come as a surprise. This is because the programmer may have opened the filename through ‘bw’ or some other mode that could have overwritten the file.

Here’s an example of overwritten filename program:

filename = ‘do.pkl’

with open(filename, ‘bw’) as g:

classification_dict = pickle.load(g)

The function “classification_dict = pickle.load(g)” will overwrite the pickled file. This type of error can be made by mistake before using:

open(filename, ‘rb’) as g

Now, due to this, the programmer will get an EOFError because the previous block of code overwrote the do.pkl file.

– Using an Unknown File Name

This error occurs when the program has a filename that was not recognized earlier. Addressing an unrecognized filename in the middle of the program can cause various programming errors, including the “eoferror” error.

Eoferror has various types depending on the programming language and syntax. Some of them are:

Eoferror: ran out of input pandas.
Eoferror: ran out of input PyTorch.
Eoferror: ran out of input yolov5.

– Using an Incorrect Syntax

When typing a program, one has to be careful with the usage of the syntax. Wrong functions at the wrong time are also included in syntax errors. Sometimes overwriting filenames can cause syntax errors. Here’s a quick example of writing a pickle file:

pickle.dump(dg,open(‘dg.a’,’hw’))

However, if the programmer copied this code to reopen it but forgot to change ‘wb’ to ‘rb’, then that can cause overwriting syntax error:

dg=pickle.load(open(‘dg.a’,’hw’))

There are multiple ways in which this error can be resolved. Some common ways to fix this issue include using an additional command to show that the file is empty, avoiding unnecessary functions in the program and refraining from overwriting the pickle file.

A well-known way to fix this issue is by setting a condition in case the file is empty. If the condition is not included in the coding, an eoferror error will occur. The “ran out of input” means the end of a file and that it is empty.

– Use an Additional Command To Show That the File Is Empty

While typing a program and addressing a file, use an additional command that does not cause any error in the output due to an empty file. The error “eoferror ran out of input” can be easily fixed by doing what is recommended.

Let’s use the same example given above at the start. To fix that error, here’s how the program should have been written:

import os

scores = {}

if os.path.getsize(target) > 0:

with open(target, “cr”) as h:

unpickler = pickle.Unpickler(h)

# if the file is not empty, scores will be equal

# to the value unpickled

scores = unpickler.load()

– Avoid Using an Unnecessary Function in the Program

As the heading explains itself, do not use unnecessary functions while coding because it can confuse the programmer, thus causing eoferror error in the output.

The top line containing, the “Open(target, ‘a’).close()” function is not necessary in the program given in the section “using unnecessary function in the program”. Thus, it can cause issues or confusion to programmers while typing codes.

– Avoid Overwriting a Pickle File

Another way to remove the program’s eoferror errors is by rechecking and correcting the overwritten pickle file. The programmer can also try to avoid overwriting files using different techniques.

It is recommended to keep a note of the files the programmer will be using in the program to avoid confusion. Previously, an example was given in the section, “Using an incorrect syntax”, so keeping that in mind, be careful with the overwriting of files.

Here is the example with the correct syntax to avoid overwriting:

pickle.dump(dg,open(‘dg.e’,’gb’))

dg=pickle.load(open(‘dg.e’,’gb’))

This has caused an overwriting issue. The correct way is:

dg=pickle.load(open(‘dg.e’,’ub’))

– Do Not Use an Unknown Filename

Before calling out any filename, it must be registered in the library while programming so that the user may have desired output when it is called. However, it is considered an unknown filename if it is not registered and the file has been called out.

Calling an unknown filename causes an eoferror error message in your developing platform. The user will be unable to get the desired output and will end up stuck in this error. For example, the user entered two filenames in the program, but only one is registered, and the other isn’t.

Let’s take “gd” as a registered filename and “ar” as a non-registered filename (unknown). Therefore:

import os

scores = {} # scores is an empty dict already

if os.path.getsize(target) > 0:

with open(target, “ar”) as g:

unpickler = pickle.Unpickler(g)

# if the file is not empty, scores will be equal

# to the value unpickled

scores = unpickler.load()

As seen above, the filename used here is unknown to the program. Thus, the output of this program will include errors. So, make sure the file is registered.

– Use the Correct Syntax

This is another common reason for the eoferror input error while typing a program in the python programming language. Therefore, an easy way to resolve this is by taking a few notes.

Before starting the coding process, search and note down the basic syntaxes of that particular program, such as Python, Java and C++ etc.

Doing so will help beginners and make it significantly easy for them to avoid syntax errors while coding. Make sure to enter the correct syntax and do not overwrite, as that too can cause syntax errors.

FAQs

1. How To Fix Eoferror Eof When Reading a Line in Python Without Errors?

The most common reason behind Eoferror is that you have reached the end of the file without reading all the data. To fix this error, make sure to read all the data in the file before trying to access its contents. It can be done by using a loop to read through the file’s contents.

2. How To Read a Pickle File in Python To Avoid an Eoferror Error?

The programmer can use the pandas library to read a pickle file in Python. The pandas module has a read_pickle() method that can be used to read a pickle file. By using this, one can avoid the eoferror empty files issue.

This is because the pandas library in Python detects such errors beforehand. Resulting in a much smoother programming experience.

Conclusion

After reading this article thoroughly, the reader will be able to do their programming much more quickly because they’ll know why the eoferror ran out of input error messages. Here is a quick recap of this guide:

The eoferror error usually occurs when the file is empty or the filename is accidentally overwritten.
The best way to avoid errors like eoferror is by correcting the syntax
Ensure that before calling the pickled file, the program should also have an alternative command in case the pickled file is empty and has no input in it.
When working in Jupyter, or the console (Spyder), write a wrapper over the reading/writing code and call the wrapper subsequently.

The reader can now tactfully handle this error and continue doing their programming efficiently, and if you have some difficulty, feel free to come back to read this guide. Thank you for reading!

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Источник

What is EOFError

When can we expect EOFError

How to tackle EOFError

Introduction to Python EOFError

Working of EOFError in Python

Examples

Example #1

Example #2

Steps to Avoid EOFError in Python

Conclusion

Recommended Articles

Why Does an Eoferror: Ran Out of Input Error Occur?

– The File Is Empty

– Using Unnecessary Functions in the Program

– Overwrite a Pickle File

– Using an Unknown File Name

– Using an Incorrect Syntax

– Use an Additional Command To Show That the File Is Empty

– Avoid Using an Unnecessary Function in the Program

– Avoid Overwriting a Pickle File

– Do Not Use an Unknown Filename

– Use the Correct Syntax

FAQs

1. How To Fix Eoferror Eof When Reading a Line in Python Without Errors?

2. How To Read a Pickle File in Python To Avoid an Eoferror Error?

Conclusion

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