In this video, I have explained how to make Python program more interactive allowing them to make their own decision depending upon the condition and execute the set of statements to perform a particular task. To know or learn more watch the video.

DECISION MAKING STATEMENTS

During the execution of the program, when there is a specific application to check the condition and make the proper decision. Decision making statements are used to anticipate specific actions which has to be taken depending upon the condition.

Decision making statements are evaluated using TRUE and FALSE values. For example, if a particular condition is TRUE what outcome is expected and when, FALSE what outcome is expected. Depending on the application of program, set of statements are written into the code to perform a particular task.

Python provides following types of decision making statements:

  • If statement: It is normal If statement which has condition in terms of Boolean expression, comparison operators, etc.
  • If..else statement: In this case, an If is followed by an else statement. It means ‘IF’ condition turns to be FALSE than ‘ELSE’ will be executed automatically
  • Ladder If.. else if .. else if: This is an extension of If..Else, where we use multiple if..else statement one after the other. In all of the following statements, only one condition will be TRUE and only that will be executed. 
  • Nested If..Else statement: This type of statement are used when you want to include If, If…else or multiple If..else into IF or ELSE condition.

This is the basic introduction regarding how to use decision making statements in Python. Let’s study each of them detail one by one with examples:

IF STATEMENT: The If statement check for the condition which can be a logical expression used to make a decision.

Syntax:

if (condition):

            Set of statements

Flowchart:

IF..ELSE STATEMENT: The If..Else statement can be explained in a manner where either of one condition will be satisfied or executed.

Syntax:

if (condition):

            Set of statements

else:

            Set of statements

Flowchart:

LADDER IF..ELSE STATEMENT: This type of statement is similar to If..Else, it just have multiple If..Else statements incorporated into a program where multiple expressions are checked for TRUE condition and set of statements are executed.

Syntax:

if (condition):

            Set of statements

elif (Condition):

            Set of statements

elif (Condition):

            Set of statements

elif (Condition):

            Set of statements

else:

            Set of statements

In this case, else statement at the last is just an alternative to all if and elif similar to that in if..else.