Math and Integer classes gone???
Hello,
I'm using the J2ME Wireless Toolkit to build my applications. For some reason it is having problems when I try using these two classes. I get a "cannot resolve symbol" error when I try using Math.round(float) and new Integer(String). Anyone know why this is happening?
Thanks,
JD
Maybe I misunderstood the original question, I thought he was asking for a function that rounded the division of a number to the closest integer. For example: 2.95 -> 3, 2.5 -> 3, 2.48 -> 2....
I have never used fixed point math so I wanted to try out that little function of yours and I put it into my app and tested it. It seems to actually be doing integer division plus a tiny bit. Then purely on a random guess I tried replacing the 1 with a y and it was now rounding the numbers in the standard way. Here is my code and test cases:
System.out.println(roundedRatio(180,39)+"-"+roundedRatio(180,40)+"-"+roundedRatio(180,41));
System.out.println(roundedRatio(180,71)+"-"+roundedRatio(180,72)+"-"+roundedRatio(180,73));
System.out.println(roundedRatio(180,119)+"-"+roundedRatio(180,120)+"-"+roundedRatio(180,121));
System.out.println(roundedRatio1(180,39)+"-"+roundedRatio1(180,40)+"-"+roundedRatio1(180,41));
System.out.println(roundedRatio1(180,71)+"-"+roundedRatio1(180,72)+"-"+roundedRatio1(180,73));
System.out.println(roundedRatio1(180,119)+"-"+roundedRatio1(180,120)+"-"+roundedRatio1(180,121));
int roundedRatio(int x, int y) {
int fpX = x << 8; // 8 is just an arbitrary number used as fixed point precision
int fpHalf = 1 << 7; // shift one space less and you get 0.5 with that fixed point precision
return ((fpX + fpHalf) / y) >> 8;
int roundedRatio1(int x, int y) {
int fpX = x << 8; // 8 is just an arbitrary number used as fixed point precision
int fpHalf = y << 7; // shift one space less and you get 0.5 with that fixed point precision
return ((fpX + fpHalf) / y) >> 8;
}float values: 180/40 = 4.5, 180/120 = 2.5 etc.
output is:
4-4-4
2-2-2
1-1-1
5-5-4
3-3-2
2-2-1
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