How to compare strings in python

Python Compare Strings – How to Check for String Equality

Ihechikara Vincent Abba

When crafting the logic in your code, you may want to execute different commands depending on the similarities or differences between two or more strings.

In this article, we’ll see various operators that can help us check if strings are equal or not. If two strings are equal, the value returned would be True . Otherwise, it’ll return False .

How to Check for String Equality in Python

In this section, we’ll see examples of how we can compare strings using a few operators.

But before that, you need to have the following in mind:

• Comparisons are case sensitive. G is not the same as g.
• Each character in a string has an ASCII value (American Standard Code for Information Interchange) which is what operators look out for, and not the actual character. For example, G has an ASCII value of 71 while g has a value of of 103. When compared, g becomes greater than G.

How to Compare Strings Using the == Operator

The == operator checks if two strings are equal. Here is an example:

We got a value of True returned because both strings above are equal.

Let’s make it look a bit more fancy using some conditional logic:

string1 = "Hello" string2 = "Hello" if string1 == string2: print("Both strings are equal") else: print("Both strings are not equal") # Both strings are equal

In the code above, we created two strings and stored them in variables. We then compared their values. If these values are the same, we would get one message printed to the console and if they aren’t the same, we would have a different message printed.

Both strings in our case were equal, so we had «Both strings are equal» printed. If we changed the first string to «hello», then we would have a different message.

Note that using = would make the interpreter assume you want to assign one value to another. So make sure you use == for comparison.

How to Compare Strings Using the != Operator

The != operator checks if two strings are not equal.

string1 = "Hello" string2 = "Hello" if string1 != string2: print("Both strings are not equal") # return if true else: print("Both strings are equal") # return if false # Both strings are equal

We’re using the same example but with a different operator. The != is saying the strings are not equal which is False so a message is printed based on those conditions.

I have commented the code to help you understand better.

How to Compare Strings Using the < Operator

This returns True because even though every other character index in both strings is equal, H has a smaller (ASCII) value than h .

We can also use conditional statements here like we did in previous sections.

How to Compare Strings Using the

Recall that this operator checks for two things – if one string is less or if both strings are the same – and would return True if either is true.

We got True because both strings are equal.

How to Compare Strings Using the > Operator

The > operator checks if one string is greater than another string.

Since the string on the left isn’t greater than the one on the right, we got False returned to us.

How to Compare Strings Using the >= Operator

The >= operator checks if one string is greater than or equal to another string.

Since one of both conditions of the operator is true (both strings are equal), we got a value of True .

Conclusion

In this article, we learned about the various operators you can use when checking the equality of strings in Python with examples. We also saw how case sensitivity can alter the equality of strings.

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How To Compare Strings in Python

You can compare strings in Python using the equality ( == ) and comparison ( < , >, != , = ) operators. There are no special methods to compare two strings. In this article, you’ll learn how each of the operators work when comparing strings.

Python string comparison compares the characters in both strings one by one. When different characters are found, then their Unicode code point values are compared. The character with the lower Unicode value is considered to be smaller.

Python Equality and Comparison Operators

Declare the string variable:

The following table shows the results of comparing identical strings ( Apple to Apple ) using different operators.

Operator	Code	Output
Equality	print(fruit1 == ‘Apple’)	True
Not equal to	print(fruit1 != ‘Apple’)	False
Less than	print(fruit1 < 'Apple')	False
Greater than	print(fruit1 > ‘Apple’)	False
Less than or equal to	print(fruit1	True
Greater than or equal to	print(fruit1 >= ‘Apple’)	True

Both the strings are exactly the same. In other words, they’re equal. The equality operator and the other equal to operators return True .

If you compare strings of different values, then you get the exact opposite output.

If you compare strings that contain the same substring, such as Apple and ApplePie , then the longer string is considered larger.

Comparing User Input to Evaluate Equality Using Operators

This example code takes and compares input from the user. Then the program uses the results of the comparison to print additional information about the alphabetical order of the input strings. In this case, the program assumes that the smaller string comes before the larger string.

fruit1 = input('Enter the name of the first fruit:\n') fruit2 = input('Enter the name of the second fruit:\n') if fruit1  fruit2: print(fruit1 + " comes before " + fruit2 + " in the dictionary.") elif fruit1 > fruit2: print(fruit1 + " comes after " + fruit2 + " in the dictionary.") else: print(fruit1 + " and " + fruit2 + " are the same.") 

Here’s an example of the potential output when you enter different values:

Output
Enter the name of first fruit: Apple Enter the name of second fruit: Banana Apple comes before Banana in the dictionary. 

Here’s an example of the potential output when you enter identical strings:

Output
Enter the name of first fruit: Orange Enter the name of second fruit: Orange Orange and Orange are the same. 

Note: For this example to work, the user needs to enter either only upper case or only lower case for the first letter of both input strings. For example, if the user enters the strings apple and Banana , then the output will be apple comes after Banana in the dictionary , which is incorrect.

This discrepancy occurs because the Unicode code point values of uppercase letters are always smaller than the Unicode code point values of lowercase letters: the value of a is 97 and the value of B is 66. You can test this yourself by using the ord() function to print the Unicode code point value of the characters.

Conclusion

In this article you learned how to compare strings in Python using the equality ( == ) and comparison ( < , >, != , = ) operators. Continue your learning about Python strings.

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