Hello in this tutorial, we will understand the string comparison in python programming.
1. Introduction
String in python language is immutable datatypes and compared with == or != operators. They are a set of characters and a string with a single character in python is known as a Character.
In python programming, if different characters are found for comparison then their Unicode values are compared and the character with a lower Unicode value is treated to be smaller. Other operators like <, <=, > and >= can also be used for string comparison and in this tutorial we will see them all in action. Make note that there are no special methods in python programming to compare the strings. Remember you use operators in python programming to perform operations on variables and values.
1.1 Setting up Python
If someone needs to go through the Python installation on Windows, please watch this link. You can download the Python from this link.
2. Python String Comparison Example
I am using JetBrains PyCharm as my preferred IDE. You are free to choose the IDE of your choice.
2.1 Python String Comparison Example
Let us understand the different string comparison operations with the help of a code snippet.
Python String Comparison Example
# python spring comparison example
# using relation operators like "==", "!=", ">", "<"
# compares the Unicode values of the characters in a string from the zeroth position till the end.
word1 = "JavaCodeGeeks"
word2 = "javacodegeeks"
# false
print("Is JavaCodeGeeks unicode equal to javacodegeeks unicode = {}".format(word1 == word2))
# true
print("Is JavaCodeGeeks unicode not equal to javacodegeeks unicode = {}".format(word1 != word2))
# false
print("Is JavaCodeGeeks unicode greater than javacodegeeks unicode = {}".format(word1 > word2))
# true
print("Is JavaCodeGeeks unicode less than javacodegeeks unicode = {}".format(word1 < word2))
print("\n==========\n")
# using is and is not
# == operator compares the 2 variables based on the actual value
# while "is" keyword compares 2 variables based on their object ids
# != operator compares the 2 variables based on the actual value
# while "is not" keyword compares 2 variables based on their object ids
string1 = "JavaCodeGeeks"
string2 = "javacodegeeks"
string3 = string1
print("Id of string1 = {}".format(hex(id(string1))))
print("Id of string2 = {}".format(hex(id(string2))))
print("Id of string3 = {}".format(hex(id(string3))))
# true
print(string1 is string1)
# false
print(string1 is string2)
# true
print(string1 is string3)
print("\n==========\n")
# user defined function
# using relation operators to compare strings by their Unicode
# <= - less than equal to
# >= = greater than equal to
def compare_str(str1, str2):
var1 = 0
var2 = 0
for i in range(len(str1)):
if "0" <= str1[i] <= "9":
var1 += 1
for i in range(len(str2)):
if "0" <= str2[i] <= "9":
var2 += 1
return var1 == var2
# false
print(compare_str("54", "102"))
# false
print(compare_str("100", "javacodegeeks"))
# true
print(compare_str("1javacodegeeks", "javacodegeeks1"))
If everything goes well the following output will be shown in the IDE console.
Console Output
Is JavaCodeGeeks unicode equal to javacodegeeks unicode = False Is JavaCodeGeeks unicode not equal to javacodegeeks unicode = True Is JavaCodeGeeks unicode greater than javacodegeeks unicode = False Is JavaCodeGeeks unicode less than javacodegeeks unicode = True ========== Id of string1 = 0x2d79e668130 Id of string2 = 0x2d79e668d70 Id of string3 = 0x2d79e668130 True False True ========== False False True
That is all for this tutorial and I hope the article served you with whatever you were looking for. Happy Learning and do not forget to share!
3. Summary
In this tutorial, we learned:
String comparisonoperators in python programming- Sample program to understand
string comparisonoperators in python programming
You can download the source code of this tutorial from the Downloads section.
4. Download the Project
This was a tutorial about string comparison in python programming.
You can download the full source code of this example here: Python String Comparison Example
