## Calculate sum of series using for

Asked by Angel Hiram Torres Mota

### Angel Hiram Torres Mota (view profile)

on 20 Jun 2019
Latest activity Commented on by James Tursa

on 20 Jun 2019

### James Tursa (view profile)

I need help to calculate the sum of this example using only for.
Thanks for the help!

James Tursa

### James Tursa (view profile)

on 20 Jun 2019
What have you done so far? What specific problems are you having with your code? This is a very simple for-loop. Do you know how to write a for-loop?
Angel Hiram Torres Mota

### Angel Hiram Torres Mota (view profile)

on 20 Jun 2019
In new to matlab and this is one of my first assignments. Im just confused at the i = m and also confused at what are my inputs. If you can recommend a book of webpage where I can learn more of this, I would also appreciate it.

### James Tursa (view profile)

on 20 Jun 2019
Edited by James Tursa

### James Tursa (view profile)

on 20 Jun 2019

Here is an outline to get you started:
a = something; % you put a value here
m = something; % you put a value here
x = something; % you put a value here
y = 0; % the starting y value
for i=1:m % the for-loop indexing
% you put code here to add something to y
end % the end of the for-loop
See the Getting Started tutorials here:

Angel Hiram Torres Mota

### Angel Hiram Torres Mota (view profile)

on 20 Jun 2019
Thanks!
Angel Hiram Torres Mota

### Angel Hiram Torres Mota (view profile)

on 20 Jun 2019
a = input("Value of a: ");
m = input("Value of m: ");
x = input("Value of x: ");
y = 0;
for i=1:m
y = ((a)*(x^i));
end
disp(y)
Like this I suppose?
I apologize again, as I said I'm new to this.
James Tursa

### James Tursa (view profile)

on 20 Jun 2019
That's a good start at getting the values in. But in the for-loop, you want to be adding terms into y. The way you have it coded now, you are simply replacing the value of y with a new term. You need to correct the code inside the for-loop.