objective-c - 将浮点向上舍入到第一个非零值

Question

伙计们，我有一些非常小的 float ，我想将其四舍五入为第一个非零值。例如:

float toRound = 0.000002125231553;
toRound = //Operations//;

toRound == 0.000002;

你有什么想法吗？

Answer 1

也许不是最好的方法。但它做你想要的;)

float s = 0.000322333123;
BOOL exit = 0;
NSString *x = [NSString stringWithFormat:@"%f", s];
for (int i = 0; i <= [x length]; i++) {
NSString *t = [x substringToIndex:i];

if ([t floatValue] == 0 || exit == 1) {
    ;;
}
else {
    exit = 1;
    s = [t floatValue];       
}
}

NSLog(@"round: %f", s);

日志:轮数:0.0003