For-Loop Midpoint Help

I'm looking to make a for-loop that looks 50 indices ahead and 50 indices behind, but the code won't precede past the line: elseif sum(count(max(i-49,1)):i,length(count)) > 1, I think it has something to do with the max function, but can't seem to work around it. Any help would be appreciated. Count is already defined as a vector of zeros or ones previously in the script.

    for i = 1:length(count);
        if sum(count(i:min(i+49,length(count)))) > 1
            count(i) = 50;
        elseif sum(count(max(i-49,1)):i,length(count)) > 1
            count(i) = 50;
        else
            count(i) = 0;
        end
    end

Answer 1

[Joseph Cheng]

since you want it to do both +50 and -50 you can't have the if/else structured that way. you'll have to do break it up. if you read about the if/elseif, it won't go into the elseif section if the first if is true

 The statements after the elseif are executed if the expression is true and all the preceding IF and elseif expressions are false

taken from the help elseif documentation.

also looking at the count as you're modifying it wouldn't after your first count(i)=50 always cause it to be 50 from then on?

[Nick]

thank you!

[Joseph Cheng]

to comment on your max statement you don't need the ,length(count) in that statement as you needed it in your min(). Also it's outside of the max function anyways.

[Joseph Cheng]

also since you look to be doing a moving window sum. look at trying something like count2 = conv(count,ones(1,100),'valid'). which i believe will do a sliding window with length 100 where it'll add up all the items. with that you can put the threshold of if the sum is greater than X put those indexes as 50.