Python if else vs if elif else: What's the Difference?

In Python, if statements are crucial for controlling the flow of a program. They allow you to execute different blocks of code based on specific conditions. There are two main types of if statements in Python: if-else and if-elif-else. This article aims to clarify the differences between these two types of statements and provide guidance on when to use each.

1. The body of the if statement is indented to differentiate it from the rest of the code. It's a good practice to use consistent indentation, such as four spaces.
2. You can use comparison operators to create the test_condition. For example, score > 50 is a test_condition that evaluates to True or False based on the value of the score variable.
3. You can use the elif (else if) clause to handle multiple conditions. The elif clause allows you to check additional conditions if the previous conditions are false.
4. You can use the logical operators (and, or, not) to create complex test_conditions.
5. It's important to handle all possible cases in your decision-making code. You can use the else clause to catch all remaining cases that are not covered by previous conditions.

IF-Else Statements:

The IF- Else statement is used when you need to choose between two alternatives. If only one statement you have to evaluate you can use the IF- Else statement. The IF-Else statement is employed to carry out a particular action when a designated condition is found to be true. In the event that the condition evaluates to false, an alternate statement within the optional else clause will be executed.

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Its syntax is as follows:

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if condition:

    # do something if the condition is true

else:

    # do something if the condition is false

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To illustrate, consider the following example:

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In this case, if the variable number is greater than 0, the output will be "The number is positive"; otherwise, it will be "The number is negative."

IF-Elif-Else Statements:

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The IF-Elif-Else statement is used when you have more than two alternatives to choose from. The use of IF-Elif statements is appropriate when you need to assess multiple statements. There is no restriction on the number of IF-Elif statements that can be utilized within a statement. The elif statement provides the capability to examine multiple expressions and execute a block of code as soon as one of the conditions evaluates to be true.

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Its syntax is as follows:

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if condition1:

    # do something if condition1 is true

elif condition2:

    # do something if condition 2 is true

else:

    # do something if both condition1 and condition2 are false

Let's consider an example that demonstrates the usage of if-elif-else:

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In this case, if the number is greater than 0, it will print "The number is positive." If the number is less than 0, it will print "The number is negative." Otherwise, if the number is equal to 0, it will print "The number is zero."

Choosing Between If-Else and If-Elif-Else:

To determine which type of if statement to use, consider the following guidelines:

Use if-else statements when the alternatives are mutually exclusive. This means that if one alternative is true, the other alternatives must be false.

Use if-elif-else statements when the alternatives are not mutually exclusive. This means that it is possible for more than one alternative to be true simultaneously.

Conclusion:

In Python, if statements play a crucial role in controlling program flow. Understanding the differences between if-else and if-elif-else statements is essential for making informed programming decisions. By following the guidelines provided in this article, you can choose the appropriate type of if statement for your specific requirements

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