Using bitwise operations to implement absolute value

Question

I'm trying to make an int array that takes in doubles from a double array, truncates the values into ints by casting, and then using bitwise operations to get the absolute value of the ints. Here's what I've got so far:

   int int_array[20];
    int o;
    for(o = 0; o<20; o++){
            int currentNum = (int) f_array[o];
            //Now use bitwise operations to get abs
            int num = currentNum;
            int y = currentNum >>31;
            currentNum = (num ^ y) - y;
            int_array[i] = currentNum;
    }

I used a print statement to print out the value of y and it seems to be working (either 0 or -1), but still when I print out int_array I seem to be getting garbage values. Any ideas? Any help is appreciated, coding in C by the way.

score 1 · Answer 1 · answered Oct 07 '17 at 19:55

1

int_array[i] should be int_array[o], you basically made a typo.

answered Oct 07 '17 at 19:55

Thorham

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Using bitwise operations to implement absolute value

1 Answers1