how to speed my code up

Hello everone,

Here, line 4 and 5 is called 5525575680 times and they last 280 and 230 seconds in order. May I speed it up, how can I use it more efficient ?

1    function  [utilization] = totalUtilization(myArray, periodNumber, count, LPP)
2       duration = 0;
3       for i = 1:count
4            duration = duration + myArray(periodNumber, i);
5       end
6       utilization = duration / LPP;
7    end

Thanks in advance.

[cglr]

Because, I still can't get used to ability of MATLAB :) .

You are exactly true and no need to loop for sum or etc. I wrote the function taking into account to your comment:

utilization = sum(myArray(periodNumber,:)) / LPP;

Thank you so much.

Answer 1

[Daniel M]

Why do you need a loop to compute a sum? Just replace the entire function with

utilization = sum(myArray(periodNumber, 1:count)) / LPP;

And if count is equal to the number of columns of myArray, replace "1:count" with just ":" to avoid making an extra temporary index.

If periodNumber happens to be a vector, then include the number 2 as the dimension input into sum.

[cglr]

Also, I would like to ask one more question.

for i=1:period

utilization(i,1) = myArray(table, i, LPP) * 100;

end

What do you offer for this loop ?

[Daniel M]

What is table in this code? Is it an empty table using the table() function? https://www.mathworks.com/help/matlab/ref/table.html

Is it a table named table? Because you're not accessing any of its properties.

If it is a regular array then no need for a loop, just replace "i" with ":"

[cglr]

actually table is a regular array with the size (period,telCount). And I can ask the question in a better way as seen below:

x = zeros(period,1);

for i=1:period

x(i,1) = sum(table(i,1:telCount));

end

Here what I want is, sum all column for each row and write result to x array.

[Daniel M]

You really enjoy writing loops! But you don't need to. Look up the documentation for the sum function. It shows you how to do just that.