My array returns all zeros. Help

So my 'resultarray' in the 'deOxygen' function gives me all zeros and I'm not sure why. The values of the pollutiondata.txt file are as follows: array =

    5.0000
    1.0000
    0.0000
   20.0000
    0.0550
    0.2000

These are rounded and I don't want them to be.

Here is my entire code:

function myHW7()
% Alex 
% December 12, 2014
% myHW7.m

load PollutionData.txt;
array = PollutionData(:,1); %#ok<NODEF>
timearray = (0:.5:250);
reshape(timearray, [501,1]);

array(3,:) = array(3,:) .* 0.001076; %conversion
array(6,:) = array(6,:) .* 0.0002778; %conversion

constant = reaeration(array);

resultarray = deOxygen(array , timearray, constant);

plot(timearray(:,1) , resultarray(:,1))
xlabel('Time after pollutant is added(hours)');
ylabel('Dissolved oxygen deficit (mg/l)');

for k1= 1:501
    if resultarray(k1) == array(1,:)
        disp(['The deficit will equal the initial deficit at time ' num2str(timearray(k1))])
    end
end

return

function constant = reaeration(array)

constant = ((array(5,1) * array(3,1)) ^ 0.5) / (array(4,1) .^ 1.5);

return

function resultarray = deOxygen(array , timearray, constant)

resultarray = zeros(1,1000);
a = (0:0.5:250);

for k1 = 1:length(a)
resultarray(k1) = (((array(6,1) .* array(2,1)) ./ (constant - array(6,1))) .* (exp(-array(6,1) .* timearray(k1) .* 3600) - exp(-constant .* timearray(k1) .* 3600))) + (array(1,1) .* exp(-constant .* timearray(k1) .* 3600));
end

reshape(resultarray, [1000,1]);

return

Any ideas?

Thanks

[Adam]

Have you tried splitting up the code in deOxygen onto multiple lines and putting a breakpoint in to see what is going on in the function?

Also please use the '{} Code' button for formatting code to make it readable (select all your text that is code and just click it)

[Alex]

what exactly should i split up? the equation of the result array you mean?

[Alex]

so i get the correct values for the array when i go through the for loop, but as soon as i go to the next point, it goes to zero. Is it possible that something is wrong with the passing the array back to the main function?

Answer 1

[Aditya Nair]

Hey! I recently encountered a similar problem. After racking my brains I realised that referencing an array incorrectly could actually make a new array whose values are set to zero. I was referencing the 1-D arrays in my 2-D array x(91,1500) as x(i) as opposed to x( i, : ) which is actually the proper way. Hope this 6 year late comment helps!