Learning Python: The Ultimate Guide for Beginners to Coding with Python with Useful Tools

Accepting Numerical Input in Python
The input() function is used when you want the user to input string; however, if you want to input
numerical value from the user, then you have to use the int() function. Let us consider the program
below that requires the user to input their age.
>>> my_age = input (“Please, What is your current age?”)

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When you write this code, the interpreter will wait until it gets a response from you. Assuming your
age is 45, the program will look like this:
>>> my_age = input (“Please, What is your current age?”)
Please, What is your current age? 45
>>> my_age
“45”
The users enter 45; however, when we request for the value of the age from the interpreter, it returns
“45”, which is an illustration of the string value we inputted. As we already know, Python interprets
the input() function as a string since the number has double-quotes. Notwithstanding, if you decide
to print only the input, that will work well. However, printing the input as a number when it is in
string format will generate an error.
>>> my_age = input (“Please, What is your current age?”)
Please, What is your current age? 45
>>> my_age
40
If you run this program, you will get an error. This is what you will see.
>>> my_age = input (“Please, What is your current age?”)
Please, What is your current age? 45
>>> my_age >=40
Traceback (most recent call last):
File “”, line 1,
TypeError: unorderable types: str() >= int()
What  happened  in  this  code  is  that  you  try  to  use  the  input()  function  to  perform  a  numerical
evaluation in line 3. Python generates an error message because you are trying to compare a string
with  an  integer  type.  The  string  in  this  situation  is  45,  which  is  assigned  to  the  variable  my_age,
which can’t be compared to the number value of 40.
To solve this issue, we have to use the int() function then informs the Python interpreter to accept it
as  a  numerical  value.  Therefore,  it  then  converts  the  “number  string”  into  a  numerical  value,  as
shown below.
>>> my_age = input (“Please, What is your current age?”)
Please, What is your current age? 45
>>> my_age >=int(my_age)
>>>my_age >= 40
True

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In  the  code  above,  when  prompted  to  enter  how  old  the  person  is,  we  entered  45.  However,  the
number is interpreted as a string, but the inclusion of the int() function helps to convert the number
string to a numerical value. With this, the interpreter then runs a conditional test to compare the age
to see if it is greater than or equal to 40. In this case, our age “45” returns true because it is greater
than 40.
How then can we use the int() function in a real program? Well, let us use a program that checks if
people are tall enough to participate in a basketball match.
basketball_height = input(“What is your current height? It should be in feet’s:”)
basketball_height = int(basketball_height)
if basketball_height >= 7:
print( “\nYou have what it takes to participate in a basketball match!”)
else:
print(“\nYou do not meet up with the requirement for this match!”)
This  program  compares  the  height  of  the  person  to  7  inches  because  we  already  convert  as  a
numerical  value.  If  the  user  inserts  anything  below  7,  the  message  “You  do  not  meet  up  with  the
requirement for this match!” will display. However, let us assume the user input 8, the output will be
as follow:
What is your current height? It should be in feet’s: 8
You have what it takes to participate in a basketball match!