Weird stuff. Please help.

Question

To convert from int to double, I usually take the easy street by multiplying 1.0 and it always work. But for this particular code:
for (int loop = 0; loop <= 9; loop++) {
double range = loop / 10.0; //this seems to be the problem. Variations include _loop * 1.0 / 10_ & _loop * 0.1_
System.out.print(range);
System.out.print(array[loop]);
}Expected Output:
_Range_                                                 _Array_
0.0                                                         array[0]
0.1                                                         array[1]
0.2                                                         array[2]
0.3                                                         array[3]
0.4                                                         array[4]
0.5                                                         array[5]
0.6                                                         array[6]
0.7                                                         array[7]
0.8                                                         array[8]
0.9                                                         array[9]But the output in my system is:
_Range_                                                 _Array_
0.0                                                         array[0]
0.1                                                         array[1]
0.2                                                         array[2]
0.300000000004                                                         array[3]
0.4                                                         array[4]
0.5                                                         array[5]
0.600000000001                                                         array[6]
0.700000000001                                                         array[7]
0.8                                                         array[8]
0.9                                                         array[9]As if the doubles are off by a weenie bit randomly.
I had tried
loop * 1.0and the result goes perfectly.
0.0
1.0
2.0
3.0
...So, whats going on?
Edited by: Tim_Tebow on May 9, 2009 8:06 PM

Answer 1

Tim_Tebow wrote:
I think formatting to one decimal point is a good idea. Where can I learn more about it?
Google?
As for learning more about floating points, here's one article: [http://www.javaworld.com/javaworld/jw-10-1996/jw-10-hood.html]
Edited by: endasil on 9-May-2009 8:11 PM