Lecture 73:-  String Comparison in Python

In Python, you can compare strings using comparison operators. String comparison is based on lexicographic (dictionary) order, where each character in the string is compared based on its Unicode code point value.

The comparison operators used for string comparison are:

1. Equality (==): Checks if two strings have the same content.

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str1 = "hello" str2 = "Hello" print(str1 == str2)   # Output: False

1. Inequality (!=): Checks if two strings have different content.

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str1 = "apple" str2 = "orange" print(str1 != str2)   # Output: True

1. Less than (<) and Less than or equal to (<=): Compares two strings lexicographically.

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str1 = "apple" str2 = "banana" print(str1 < str2)    # Output: True print(str1 <= str2)   # Output: True

1. Greater than (>) and Greater than or equal to (>=): Compares two strings lexicographically.

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str1 = "banana" str2 = "apple" print(str1 > str2)    # Output: True print(str1 >= str2)   # Output: True

Keep in mind that string comparison is case-sensitive, meaning uppercase characters are considered "less than" lowercase characters based on their Unicode values.

If you want to perform case-insensitive string comparison, you can convert both strings to lowercase or uppercase using the lower() or upper() methods before comparing them.

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str1 = "Hello" str2 = "hello" print(str1.lower() == str2.lower())   # Output: True

It's important to remember that when comparing strings, their contents are compared, not their memory addresses. So even if two strings have the same content but are stored in different memory locations, the comparison will still yield the correct result.

String comparison is a fundamental operation in Python, and it allows you to compare and make decisions based on the contents of strings in your code.