For loop doesn't doesn't summate

Month and data are imported tables. n==1 means that it is January, the purpose is to add to "number" with a value corresponding to the month but when I run I still get number=0. What is wrong with this code?

number=0;
for n=Month
        if n==1
            number=number+data(n);
        end 
end 

Answer 1

[Image Analyst]

number is overwritten every iteration so it will take on only the value from the last iteration. If it's zero at the end then data(Month(end)) must have been -1. To not overwrite, do

number = data; % Initilize number;
% Find out what indices have data == 1.
valueIs1 = Month == 1;
number(valueIs1) = 2; % Add 1 to all indices where value is 1, which makes them 2.

If you need help, attach Month and data

save('Answers.mat', 'Month', 'data');

Use the paperclip icon to attach the .mat file.