Python divide string by symbol

How to Split a String Between Characters in Python

In this guide to splitting strings in Python, we’ll explore the various ways we can use the language to precisely split a string. When we split strings between characters in Python, it’s possible to extract part of a string from the whole (also known as a substring).

Learning how to split a string will be useful for any Python programmer. Whether you intend to use Python for web development, data science, or natural language processing, splitting a string will be a routine operation.

We’ll follow several procedures for obtaining substrings in Python. First, we’ll take a look at splice notation and the split() function. Afterwards, we’ll examine more advanced techniques, such as regex.

Split a String Between Characters with Slice Notation

When it comes to splitting strings, slice notation is an obvious choice for Python developers. With slice notation, we can find a subsection of a string.

Example: Split a string with slice notation

text = """BERNARDO Well, good night. If you do meet Horatio and Marcellus, The rivals of my watch, bid them make haste.""" speaker = text[:8] print(speaker) 

Split a String by Character Position

To use this method, we need to know the start and end location of the substring we want to slice. We can use the index() method to find the index of a character in a string.

Example: How to find the index of a character in a string

sentence = "Jack and Jill went up the hill." index1 = sentence.index("J",0) print(index1) index2 = sentence.index("J",1) print(index2) 

A Quick Guide to Using split()

The Python standard library comes with a function for splitting strings: the split() function. This function can be used to split strings between characters. The split() function takes two parameters. The first is called the separator and it determines which character is used to split the string.

The split() function returns a list of substrings from the original string. By passing different values to the split() function, we can split a string in a variety of ways.

Splitting Strings with the split() Function

We can specify the character to split a string by using the separator in the split() function. By default, split() will use whitespace as the separator, but we are free to provide other characters if we want.

Example: Splitting a string by whitespace

sentence = "The quick brown fox jumps over the lazy dog." # split a string using whitespace words = sentence.split() print(words) 

['The', 'quick', 'brown', 'fox', 'jumps', 'over', 'the', 'lazy', 'dog.']

Example: Splitting a string separated by commas

rainbow = "red,orange,yellow,green,blue,indigo,violet" # use a comma to separate the string colors = rainbow.split(',') print(colors) 

['red', 'orange', 'yellow', 'green', 'blue', 'indigo', 'violet']

Use split() with Multiple Arguments

Using the split() function, we also can control how many lines of text are split. This function takes a second parameter: maxsplit. This variable tells the split() function how many splits to perform.

Example: Splitting multiple lines of text

text = """HORATIO Before my God, I might not this believe Without the sensible and true avouch Of mine own eyes.""" lines = text.split(maxsplit=1) print(lines) 

['HORATIO', 'Before my God, I might not this believe\nWithout the sensible and true avouch\nOf mine own eyes.']

Because we set maxsplit to a value of 1, the text was split into two substrings.

How to Split a String Between Two Identical Characters

If we have a text that is divided by multiple identical characters, we can use the split() function to separate the strings between the characters.

Example: Using symbols to separate a string

nums = "1--2--3--4--5" nums = nums.split('--') print(nums) 

How to Find a String Between Two Symbols

We can combine the index() function with slice notation to extract a substring from a string. The index() function will give us the start and end locations of the substring. Once we know the location of the symbols ($’s in this case), we’ll extract the string using slice notation.

Example: Extracting a substring with the index() function

# extract the substring surrounded by $'s from the text text = "Lorem ipsum dolor sit amet, $substring$ adipisicing elit." start = text.index('$') end = text.index('$',start+1) substring = text[start+1:end] print(f"Start: , End: ") print(substring) 

Start: 28, End: 38 substring 

How to Use Regular Expression to Split a String Between Characters

Regular Expression is a convenient way of searching a string or text for patterns. Because regular expression patterns (regex) are so versatile, they can be used to create very targeted searches.

Python comes with the re library. With regex, we can search text with a fine tooth comb, looking for specific words, phrases, or even words of a certain length.

Example: Using a regular expression to search for a string

import re text="""The Fulton County Grand Jury said Friday an investigation of Atlanta's recent primary election produced "no evidence" that any irregularities took place.""" # search the text for words that are 14 characters long match= re.search(r"\w", text) print(match.group()) # search the text for the word "Atlanta" atlanta = re.search(r"Atlanta",text) print(atlanta.group()) 

Example: Using regex to find a date

sentence= "Tony was born on May 1st 1972." date= re.search(r"\d",sentence) print(date.group()) 

In the examples above, we employed the search() method to find a substring using regular expression patterns. This method has two arguments. The first is our regex pattern, and the second is the string we’d like to perform the search on.

Regular expression uses special characters and numbers to create targeted searches. For instance, our first example uses the special characters \w to search for words.

Special Characters for Regular Expressions:

• /w – Searches for alphanumeric characters (words)
• /d – Searches for digit characters (0-9)
• /s – Search for whitespace characters

Example: Find if a string starts with a word with regex

speech= """HAMLET O God, your only jig-maker. What should a man do but be merry? for, look you, how cheerfully my mother looks, and my father died within these two hours.""" match= re.search(r"^HAMLET",speech) print("HAMLET" in match.group()) 

Furthermore, we can use regex to find a string between two characters. In the next example, we’ll use a regex pattern to find a string between square brackets.

Example: Regular expression to find all the characters between two special characters

speech="""KING CLAUDIUS [Aside] O, 'tis too true! How smart a lash that speech doth give my conscience!""" match = re.search(r"(?<=\[).+?(?=\])",speech) print(match.group()) 

Regex includes many metacharacters. Covering them all is outside the scope of this tutorial, but here are a few more from the examples above.

More Regex Metacharacters

• \ – Use to escape a special character (for instance, the [ character)
• . – Wildcare character (matches any character except the newline character)
• + – Matches multiple occurrences
• ? – Markes the preceding character as optional

Split a String Using a Slice Object

A Python slice object is used to split a sequence, such as a string or list. The slice object tells Python how to slice the sequence.

Slice objects take three parameters: start, stop and step. The first two parameters tell Python where to start and end the slice, while the step parameter describes the increment between each step.

With a slice object we can get a substring between characters. To create a slice object, use the slice() function. This function returns a new slice object that can be applied to a string, or other sequence.

Example: Using a Slice Object to get a substring

text="""To be, or not to be, that is the question, Whether 'tis nobler in the mind to suffer""" x = slice(19) words = text[x] print(words) 

Summary

This guide explored several techniques for splitting strings between characters. The easiest solution for this task will often be slice notation, but this isn’t always true. Depending on your needs, it may be necessary to employ other Python methods in order to achieve your goals.

Here’s a quick review of the topics we covered:

• With the split() function, we can split strings into substrings.
• If you need a very targeted search, try using regular expressions.
• Slice Objects are another option for slicing strings.
• Slice notation is a quick way to split a string between characters.

You can think of each option as a tool in the Python developer’s toolbox. Remember to use the appropriate tool for the job and you’ll be on the right track.

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Python Split String By Character – Split String Using split() method

Hi everyone, in this Python Split String By Character tutorial, we will learn about how to split a string in python. Splitting string means breaking a given string into list of strings. Splitting string is a very common operation, especially in text based environment like – World Wide Web or operating in a text file. Python provides some string method for splitting strings. Let’s took a look how they works.

Python Split String By Character Tutorial – Getting Started With Examples

When splitting string, it takes one string and break it into two or more lists of substrings. Some time we may need to break a large string into smaller strings. For splitting string python provides a function called split().

What Is split() function ?

• split() method breaks a given string by a specified separator and return a list of strings.

• Separator is a delimiter at which the string splits. If the separator is not specified then the separator will be any whitespace. This is optional.
• Maxsplit is the maximum number of splits.The default value of maxsplit is -1, meaning, no limit on the number of splits. This is optional.

Splitting String By Whitespace

If we don’t specify any separator split() method takes any whitespace as separator.

Let’s understand it with an example.

So the output of this code is –

In the output, you can see that the string is broken up into a list of strings.

Splitting String By Colon ‘ : ‘

Now we will use : as a separator. Let’s see what happend.

You can see that the colon(:) has been removed and string is splitted.

Splitting String By Hash Tag ‘ # ‘

Now we will use # as a separator, so for this the code is following.

Let’s see the result

All the # has been removed and string is splitted into list of substrings.

Splitting String By Comma ‘ , ‘

Now let’s see how to split string by comma. So write the following code.

Splitting String By Position

Now if you want to split a string at particular position. For example string is “PythonIsProgrammingLanguage” , and you want to split this string at 4th position. So the code for this will be as follows –

You can see the string is broken up from 4th position and splitted into list of substrings.

Splitting String By A Particular Characters

Now we will split string by a particular character. Let’s take an example “Python Is Programming Language”, and now you have to split this string at character P . So code for this is like below.

• Here we have used P as a separator, so the result is as follows.

• All the P character has been removed from this string but whites paces are still in there because separator is a character.

Splitting String By Special Characters

Now we will see how to split string by special characters like \n, \t and so on. Let’s implement it in examples.

• Here i am taking a special character \t i.e., tab.
• This code will split string at \t .
• So see the result.

Splitting String By Maxsplit

Now we will see splitting string by maxsplit. It is a number, which tells us to split the string into maximum of provided number of times. So let’s move towards its implementation.

Now we will take an another example in which we will specify both separator as well as maxsplit.

And the output of this example is –

• We can see that when value of maxsplit is 4 then string is splitted into a list of substrings where first four string is splitted at # and remaining are same.
• When value of maxsplit is 1 then string is splitted into a list of substrings where only first string is splitted at # and remaining are same.
• When maxsplit is 0 then no splitting occur because the value is zero.

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So friends, now i am wrapping up Python Split String By Character tutorial. If you have any query then please let me know this. And please share this post with your friends and suggest them to visit simplified python for best python tutorials. Thanks Everyone.

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