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Python: Input a number, if it is not a number generates an error message

Python Basic: Exercise-113 with Solution

Write a Python program to input a number, if it is not a number generates an error message.

Sample Solution-1:

Python Code:

while True:
    try:
        a = int(input("Input a number: "))
        break
    except ValueError:
        print("\nThis is not a number. Try again...")
        print()
		
		

Sample Output:

Input a  number: abc                                                                                          
                                                                                                              
This is not a number.  Try again...                                                                           
                                                                                                              
Input a  number: 150 

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Sample Solution-2:

Python Code:

x = 1.23
x_int = x.is_integer()
print("Check if x is an integer!")
print(x_int)
y= 1.0
y_int = y.is_integer()
print("Check if y is an integer!")
print(y_int)  

Sample Output:

Check if x is an integer!
False
Check if y is an integer!
True

Visualize Python code execution:

The following tool visualize what the computer is doing step-by-step as it executes the said program:


Sample Solution-3:

Python Code:

x = 1.0
x_int = isinstance(x, int)
print("Check if x is an integer!")
print(x_int)
y = 1
y_int = isinstance(y, int)
print("Check if y is an integer!")
print(y_int)

Sample Output:

Check if x is an integer!
False
Check if y is an integer!
True

Visualize Python code execution:

The following tool visualize what the computer is doing step-by-step as it executes the said program:


Python Code Editor:

 

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Python: Tips of the Day

Unpack variables from iterable:

# One can unpack all iterables (tuples, list etc)
>>> a, b, c = 1, 2, 3
>>> a, b, c
(1, 2, 3)

>>> a, b, c = [1, 2, 3]
>>> a, b, c
(1, 2, 3)