To evaluate multiple conditions we use nested if statement. The general form is
Syntax
if test condition1:
if test condition2:
statement1
else:
statement2
else:
statement3
From the above syntax if the condition1 is true control transfers to condition2 when it is true statement 1 executes, oterwise statement 2 will be executed.If the condition1 itself false the control will be transferred to else part and statement3 will be executed.
If statement: If statement evaluates the test condition and will execute statement-block only if the condition is True. If the condition is False, the statement-block is not executed and control is transferred to next statements. The group of statements which has to be executed when the condition is true are written in statements-block. Statement-block may be a single statement or group of statements with proper indent.
Flow chart :
Ex: Python program to check whether the given number is positive or not
num = float(input("Enter a number: "))
if num > 0:
print("Positive number")
print("Simple if")
Output:
Enter a number 5
Positive number
Simple if
If –else:
The if-else is an extension of the simple if statement. The if –else statement evaluates the condition, whether the condition is true then the If block will be executed otherwise the else block will be executed, not both. The general form is
if test condition:
If block
else:
else block
statement-x
num = float(input("Enter a number: "))
if num > 0:
print("Positive Number ")
else:
print("Negative Number ")
Output:
Enter a number 5
Positive Number
