In previous two articles, we discussed conditional statements such as
if-then-else. All of those previous structures are using one conditions only, what if, we want to check multiple conditions at different time and make decisions based on the output of those conditions. The python has a special
if-then-elif-else construct to check multiple conditions one after another. Look at the figure below to understand this logic better.
The first condition,
condition 1 is the if-block and if true then executes the
block A and if false will move to the next condition, which is
condition 2 is true that will execute
block B and if it is false then move to
condition 3. The
condition 3 if true will execute the
block C and if everything is false, the final output is
Note that the condition 1 comes from if-block, condition 2 comes from elif, condition 3 is elif and else block is D.
Example – If-then-elif-else
In this example, student receive his grade in A, B, C , D , E, and F.
A = Excellent
B = Outstanding
C = Very Good
D = Good
E = Fair
F = Fail.
We need to print the result based on the grade that the student gets. Consider the following code.
grade = input("Enter Your Grade:" ) if grade == "A": print("You grade is Excellent!") elif grade == "B": print("Your grade is Outstanding!") elif grade == "C": print("Your grade is Very Good!") elif grade == "D": print("Your grade is Good!") elif grade == "E": print("Your grade is Fair..Work Hard!") elif grade =="F": print("Your Failed.. Try again later") else: print("Wrong Input")
The output of the program is given below.
Output – If-then-elif-else
=========== RESTART: C:/Python_projects/Display_Student_Result.py =========== Enter Your Grade:D Your grade is Good! >>>