Writing MATLAB program

Program Statements:

• Firstly, a menu is displayed which gives an option for user to select whether factorial is to be calculated by function or without function.
• Prompt the user to enter a choice and number n.
• Input choice and n whose factorial is to calculated.
• If choice is 2, calculate factorial without function
  • Use for loop that iterates from value 1 to n and calculate factorial.
• Else if choice is 1 then calculate the factorial with function
  • Call a function fact with the argument k.
  • Then the print the factorial of the number.
• Function definition of fact contain below statements:
  
  • The base condition returns 1 when number becomes 1
  • Second condition will goes on until the factorial of the number is calculated using recursive call.

MATLAB code to find factorial of a number using function and without using function: 

disp("1  for factorial using function");

disp("2 for factorial without function");

// These two will show the menu

ch=input("enter a choice");
n = input("enter a number for fact");

// This will take the number from user

if (ch==2)
f = 1;
for i = 1:n // loop from 1 to n
    f = f*i; // multiplying until i=n
end // end for loop

else if(ch==1)

k=n
  kFactorial = fact(k); // function call
  fprintf('%d! = %d\n', k, kFactorial); 

// Prints factorial

    else 
        disp("select correct option");
        
    end
    end

function x = fact(n) // function definition
if n<=1 // goes when n<=1
  x = 1;
else
  x = n .* fact(n-1) ; // recursive function call
end
end