# Create a program that asks a user to input a number and then finds the sum of digits of the number using recursion. for example 341 = 3+4+1 = 8

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123 on 17 Mar 2018
This is what i have but it wont compute anything..
number = input('Enter a number here:');
function result = mySum(numbers)
numbers = num2str(number) - '0';
if length(numbers) == 0
result = 0;
else
result = numbers(end) + mySum(numbers(1:end - 1));
end
end

vijaya lakshmi on 20 Mar 2018
Hi Matt,
You have written function definition but missed to call the function 'mySum', that is why it is unable to compute anything.
You can refer to the following code snippet to achieve this
numbers=input('get a number');
numbers = num2str(numbers);
out=mySum(numbers)
function result = mySum(numbers)
result=0;
for i=1:length(numbers)
result=str2double(numbers(end))+mySum(numbers(1:end-1));
end
end
Hope this helps you!

Saptarshi Neogi on 30 Aug 2020
Edited: Saptarshi Neogi on 30 Aug 2020
% This program does not require any inbuilt functions.
function x = digit_sum(n)
x=0;
if n>0
x=mod(n,10)+digit_sum(floor(n./10));%recursive
end
Diego Sánchez Saldaña on 30 Dec 2020
Very nice and useful answer! thank you so much!