1000 by 1000 for loop in android sep

Question

I have a code like this running on Android 2.3.3 (Nexus One)

for(i=0; i<1000; i++){
    for(j=0;j<1000;j++){
         do AND calculation
         do XOR calculation
    }
}

Is this too much calculation for android? I went through the debugger and the debugger lost its control after 3 iteration of the first for loop (3000 iteration total)

I am running this on a new thread like this and call this function on main ui thread..

public void startCalculation(ArrayList<data> featA, ArrayList<data> featB){

    newThread= new Thread(new Runnable(){
        public void run(){
            theFunction();
        }
    });
    newThread.start();
}

Thanks in advance...

It doesn't give me any error message but I wasn't able to step through the process and also I wasn't able to see the variables on the debugging tool — codereviewanskquestions, May 25 '11 at 11:23
for debuging use Logcat ... just add code `Log.d("Tag", "Value to debug:" + value);` in loop and read values from Logcat's window in Eclipse — Selvin, May 25 '11 at 11:44
After the first iteration, it prints something like this about 10 lines and terminates the app CG_EXPLICIT freed 200k, 54% free 2767K/5959K, external — codereviewanskquestions, May 25 '11 at 11:52
you have for(j=0; **i** <1000;j++) not for(j=0;j<1000;j++) in your code ? — Selvin, May 25 '11 at 14:27

score 3 · Accepted Answer · answered May 25 '11 at 11:24

3

Yeah it seems likely that the process monitor killed your application because it was unresponsive. Keep long running operations off the UI thread.

answered May 25 '11 at 11:24

fleetway76

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Selvin · Answer 2 · 2011-05-25T11:46:28.213

2

Do not do this on UI thread ... use Threads or AsyncTasks for long running operations

EDITed:

for debug use logcat ... just add

Log.d("Some My Tag", "Debuging value of smth is:" + value);

and then read values from Logcat's window in Eclipse

edited May 25 '11 at 11:46

answered May 25 '11 at 11:22

Selvin

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score 1 · Answer 3 · edited May 23 '17 at 10:34

1

You will get a ANR (Application not responding) error if you carry out long running operations on the UI thread. You should do your heavy duty work in background threads.

edited May 23 '17 at 10:34

Community

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answered May 25 '11 at 11:24

thumbmunkeys

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you didnt say in your original question that you run it in a thread... what happens inside of your loop then, are you doing memory intensive things? – thumbmunkeys May 25 '11 at 15:39

1000 by 1000 for loop in android sep

3 Answers3