Page 242 - Computer Science Class 11 With Functions
P. 242
Sample Output:
>>> Enter the Strings:Madras
2
10.3.2 Factorial of a Number
Given a non-negative integer n, we wish to compute its factorial (n!).
We write a function to compute the factorial (n!) of a number n (>=0).
The function factorial accepts a positive integer as an argument and returns its factorial. We are aware that each of
0! and 1! equals 1.
To compute the factorial of a number (positive integer), we compute the product of positive integers up to n. For
example, to compute 6!, we compute the product 1*2*3*4*5*6. Thus, to compute 6!, we initialise the product to be
1, and for each number in the range(1,7), we multiply the product by it.
Note that the function range(1,7) returns a sequence of six integers: 1, 2, 3, 4, 5, 6.
In general, to compute n!, we compute the product 1*2*...*n of the numbers in the range(1,n+1).
Program 10.3 accepts a non-negative integer from the user and invokes the function factorial() to compute and
display its factorial.
Program 10.3 Compute and display n! for a number n, entered by the user.
01 def factorial(n):
02 '''
03 Objective: To compute factorial of a number
04 Input Parameter: n - numeric value
05 Return Value: factorial of n - numeric value
06 '''
07 product = 1
08 for i in range(1, n + 1):
09 product = product * i
10 return product
11 '''
12 User Interface:
13 Accept a number from the user interactively,
14 and display its factorial
15 '''
16 n = int(input('Enter a non-negative integer: '))
17 #ensure n is an integer and n>=0
18 assert n >= 0
19 product = factorial(n)
20 print('Factorial of', n, 'is', product)
Sample Output:
>>> Enter a non-negative integer: 6
Factorial of 6 is 720
Assert condition is the expression that is expected to be true. If the condition evaluates to False, an Assertion Error
is raised, and the program execution is halted.
10.3.3 Multiplication Table of a Number
Program 10.4 Write a function that accepts the number n whose multiplication table is to be printed as an argument
and prints its multiplication table.
To do so, we only need to multiply the given number by each number in the range(1, 11) and print the product.
240 Touchpad Computer Science-XI

