Copying strings in python

Copying Strings in Python: A Step-by-Step Guide

To simplify the process, treating the strings as lists of characters and utilizing list comprehension to create the output string would be a more efficient solution. Another approach could involve the use of regular expressions, which could prove helpful in certain situations. On each iteration, if the character is a space, append a space to the output string. It should be noted that this method may not be the most efficient as strings are immutable and a new object is created each time. Otherwise, add the character at that index to the output string.

How to copy a string to another string in python

Constructing the output string would be simpler by treating the strings as character lists and utilizing list comprehension.

output = ''.join([c*2 if c in s2 else c for c in s1]) 

How do I get a substring of a string in Python?, One is (start, length) and the other is (start, end). Python’s (start, end+1) is admittedly unusual, but fits well with the way other things in Python work. A common way to achieve this is by string slicing. MyString [a:b] gives you a substring from index a to (b — 1). Code sample>>> x = «Hello World!»>>> x[2:]’llo World!’>>> x[:2]’He’Feedback

How to copy changing substring in string?

You could use a regular expression:

import re string = '"edge_liked_by":' number = re.search(r'', string).group(1) 

The usefulness of regular expressions varies depending on the situation.

To extract the digits from the string regardless of their position, the following steps can be followed:

import re def get_string(string): return re.search(r'\d+', string).group(0) >>> get_string('"edge_liked_by":') '128' 

To exclusively acquire digits located at the tail end of the string, an anchor can be utilized to guarantee that the output is obtained from the farthest end. The subsequent instance will capture any uninterrupted string of numbers that is preceded by a colon and culminates within 5 characters of the string’s termination.

import re def get_string(string): rval = None string_match = re.search(r':(\d+).$', string) if string_match: rval = string_match.group(1) return rval >>> get_string('"edge_liked_by":') '128' >>> get_string('"edge_liked_by":') '1' 

By adding a colon to the above example, we ensure that only values are selected and that keys such as «1321» are not matched, which I inserted as a test.

To extract the content after the final colon but without including the bracket, you can combine slicing with split.

>>> '"edge_liked_by":'.split(':')[-1][0:-1] '128' 

As it appears to be a JSON object, you may enclose the string with curly brackets to transform it into a nested dictionary, enabling you to perform queries.

>>> import json >>> string = '"edge_liked_by":' >>> string = '' >>> string = json.loads(string) >>> string.get('edge_liked_by').get('count') 128 

The initial two will result in a string, whereas the last one will be interpreted as a JSON object and return a number.

It appears that the string type you are dealing with is obtained from JSON, possibly as a result of utilizing an API.

Atomizing JSON data into a string may not be the best approach. It is recommended to use the original output instead, if possible.

In case it doesn’t resemble JSON, I would modify it to appear JSON-like. This can be done by enclosing it in <> and utilizing the json.loads package.

import json string = '"edge_liked_by":' string = "" json_obj = json.loads(string) count = json_obj['edge_liked_by']['count'] 

By using count , you can achieve the expected result. In my opinion, this approach is better than utilizing regular expressions because it allows you to depend on the data’s arrangement and reuse the code for parsing other attributes easily. In contrast, if you opt for regular expressions, you will need to adjust the code for decimal, negative, or non-numeric data, making it less intuitive.

How to copy a string to another string in python, How to copy a string to another string in python. I have two strings, s1 and s2, and I need to find if there are letters in common in both of them and make it double for example: s2=»lo» s1=»Hello World» def Str_dup (s1,s2): s3=str () d=dict () for i in s2: d [i]=True print i w=0 for w in range (len (s1)): if d [s1 [w]]: s3 …

How to copy spaces from one string to another in Python?

Populate a placeholder list with relevant characters and merge it following the utilization of str.join .

it = iter(string2) output = ''.join( [next(it) if not c.isspace() else ' ' for c in string1] ) 

print(output) 'ESTD TD L ATPNP ZQ EPIE' 

This method is effective because it prevents the need for repetitive string concatenation.

It is necessary to use enumerate() to loop through the indexes and characters in string1 .

During each iteration, when encountering a space character, append a space to the output string. It’s worth noting that this method is inefficient since it involves creating a new object, given that strings are immutable. Otherwise, append the character found at that specific index in string2 to the output string.

So that code would look like:

output = '' si = 0 for i, c in enumerate(string1): if c == ' ': si += 1 output += ' ' else: output += string2[i - si] 

It would be more effective to utilize a generator with str.join instead of relying on a comparable method that involves sluggish concatenations to the output string.

def chars(s1, s2): si = 0 for i, c in enumerate(s1): if c == ' ': si += 1 yield ' ' else: yield s2[i - si] output = ''.join(char(string1, string2)) 

You can try insert method :

string1 = "This is a piece of text" string2 = "ESTDTDLATPNPZQEPIE" string3=list(string2) for j,i in enumerate(string1): if i==' ': string3.insert(j,' ') print("".join(string3)) 

How can I copy a Python string?, You don’t need to copy a Python string. They are immutable, and the copy module always returns the original in such cases, as do str(), the whole string slice, and concatenating with an empty string.. Moreover, your ‘hello’ string is interned (certain strings are).Python deliberately tries to keep just the one copy, as that …

Python copy all lines before string in another text file

The intention behind your actions is unclear. Based on the information provided and the sample input file, it appears that you desire the outputt to contain the following.

This is the house this is the flower this is a tree 

def transform(inputt, outputt): with open(inputt) as f, open(outputt, "w") as f1: f1.write(f.read().split("***")[0]) 

It’s difficult to understand your requirements without a more detailed explanation, although this code contains multiple drawbacks.

After taking into consideration the feedback provided in the comments, an edit has been made.

def transform(inputt, outputt_base): with open(inputt, "r") as f: for count, block in enumerate(f.read().split("***")): outputt_name = outputt_base + "_.txt".format(count) with open(outputt_name, "w") as f1: f1.write(block) 

Assuming that the input file provided as an example contains output , the program will generate two output files.

This is the house this is the flower this is a tree 

This is a car this is an apple this is the nature 

How to Substring a String in Python, Python offers many ways to substring a string. This is often called «slicing». Here is the syntax: string [start:end:step] Where, start: The starting index of the substring. The character at this index is included in the substring. If start is not included, it is assumed to equal to 0. end: The terminating index of the …

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Python Copy String

Working with strings is such a task that a developer has to perform at all levels of skills and most people when they are starting, have issues with strings. One crucial step that is often performed by the user is to copy a string from one variable to another. In Python, this can be done by using different techniques such as the assignment operator, concatenation of the entire string, concatenation of characters, and the slice() method.

This post will cover all of the methods that the user can use to copy strings in Python.

Method 1: The Assignment Operator

In other programming languages, when the assignment operator “=” is used to create a copy of a string, it actually creates a reference link instead of a copy. When a change is made to the first string, a change is also made in the copy due to the reference link. However, that is not true in the case of Python. Therefore, the easiest possible way to copy the string in python is to use the assignment operator.

To demonstrate this, take the following code snippet:

x = «This is LinuxHint!»
y = x

When this code snippet is executed, it produces the following result on the terminal:

As you can see clearly, you have successfully copied strings in Python.

Method 2: Using Concatenation With an Entire String

Alternative to the first method, the user can create an empty string variable and then use the concatenation operator “+” to copy one string to another. To do this, use the following code snippet:

x = «This is LinuxHint!»
y = «»
#String Concatenation
y = y+x
#Print Both Strings
print ( «The Original String: » , x )
print ( «The Copied String: » ,y )

When this code is executed, it will display the following outcome on the terminal:

The output verifies that the string has been successfully copied to another string variable.

Method 3: Character Concatenation Through Loop

Instead of concatenating the entire string at once, the user can choose to do it one character at a time. For this, the user will require to use a loop that will allow him to iterate through every character in the string to be appended to the string. To demonstrate this, take the following code:

x = «This is Character Concatenation»
y = «»
#One by One Character Concatenation
for char in x:
y = y + char
#Print Both Strings
print ( «The Original String: » , x )
print ( «The Copied String: » ,y )

When this code is executed, it procure the following results:

It can be easily seen that the string has been copied.

Method 4: Using String Slicing Method

Lastly, the user can use the string slicing technique to return the entire string to a new variable. String slicing is essentially a way of subtracting a substring from a string by passing in the starting and ending index values of the substring. But if the values are left empty, it copies the entire string. To demonstrate this, take the following code example:

x = «This is String Slicing»
y = x [ : ]

print ( «The Original String: » , x )
print ( «The Copied String: » ,y )

When this code snippet is executed, it shows the following outcome:

The output verifies that the string has been copied to another variable.

Conclusion

Copying a string from one variable to another variable is rather an easy task that can be performed using the assignment operator, the concatenation operator, and the string slicing technique. In Python, when the string is copied from the mentioned methods, then it doesn’t create a reference link to the original string. This means that any changes made to the original string will not affect the copied string.

About the author

Abdul Mannan

I am curious about technology and writing and exploring it is my passion. I am interested in learning new skills and improving my knowledge and I hold a bachelor’s degree in computer science.

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Copying strings in python

Today, on this page, we are going to learn how to copy strings in Python. Before we start I want to tell you some important things that should be in your mind. So, Maybe you know that, in Python, strings are immutable, that’s means you can’t change any value in Python programming. In simple words, it means that a string cannot directly have a copy.

If you have a new variable that is declared a value and if you directly assigned the value, so, remember that this would not make a copy of original string instead, both of the created variables would be the same string.

How to Copy Strings in Python

Empty String to Get a Copy String in Python

We have started with a simple method that is empty string this is very easy to implement jsut you need to add empty string with original by using the concatenation operator while you are calling a new variable you can see the code below.

string = 'wholeblogs' empty_string = ' ' + string print(empty_string)

Slicing to Copy a String in Python

Everybody know that the slice and : operator can be use to utilize the slice value and ganerate a new one. Original string would be copied intact to the new variable. if both these not passed you can see the code below!

ostr = 'wholeblogs' nstr = ostr[:] print(nstr)

str() Function to Copy a String in Python

You can easily use the str() function if you need to pass out on string will returen one copy of that string. follow the code below.

ostr = ‘Wholeblogs’
nstr = str(ostr)
print(nstr)

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