FloatProcessor- num: float+round_to_two_decimals() : float+format_to_two_decimals() : str+floor_to_two_decimals() : float 旅行图 让我们用一个旅行图的示例来说明使用上述三种方法处理浮点数的过程: 使用round函数 FloatProcessor->FloatProcessor FloatProcessor->FloatProcessor FloatProcessor-->FloatP...
1.function returnFloat(value){},参数是要被转换的数字。 2.var value=Math.round(parseFloat(value)*100)/100,这个应该是函数的核心之处,parseFloat(value)将参数转换为浮点数,因为参数有可能是字符串,乘以100是因为要保留两位小数,先将小数点向右移动两个位数,然后再利用Math.round()方法实行四舍五入计算,最后...
Round to 2 decimal places using the round() function The round() function is Python’s built-in function for rounding float point numbers to the specified number of decimal places. You can specify the number of decimal places to round by providing a value in the second argument. The example...
return Decimal(str(n)).quantize(Decimal(s), rounding=ROUND_HALF_UP) print(round_dec(3.545,2)) # 保留两位小数 def myRound(res): if res=="" or res==0: returnData=0.00 else: if isinstance(res,float): new_res=res*100 returnData=round(new_res)/100 elif isinstance(res,str): new_re...
python2和python3的doc中都举了个相同的例子,原文是这么说的: NoteThebehavior of round()forfloats can be surprising:forexample,round(2.675,2)gives2.67instead of the expected2.68.Thisisnota bug:it’s a result of the fact that mostdecimalfractions can’t be represented exactlyasafloat.SeeFloatingPoi...
2.68. This is not a bug: it's a result of the fact that most decimal fractions can't be represented exactly as afloat. See Floating Point Arithmetic: Issues and Limitations for more information. 简单的说就是,round(2.675, 2) 的结果,不论我们从python2还是3来看,结果都应该是2.68的,结果它...
the result depends on...(对于近似值,则依赖于底层的C函数库,在很多系统中ROUND函数会使用“取最近的偶数”的规则) 通过这两条规则,我们可以看出,由于我们在使用两个字段相乘的时候,最终的结果是按照float类型处理的,而在计算机中...从field5和field6执行ROUND函数的结果可以明确的看确实是转换为了最近...
decimal是Python核心库用于实现高精度小数运算模块。对比原生的float类型,Decimal类型能更好地保证计算精度,特别是货币计算或涉及其他高精度计算的场景。 rounding参数取值ROUND_HALF_UP, from decimal import Decimal, ROUND_HALF_UP In [127]: Decimal("3.124").quantize(Decimal("0.00"), rounding=ROUND_HALF_UP)...
as number.NoteThe behavior of round() for floats can be surprising: for example, round(2.675, 2) gives 2.67 instead of the expected 2.68. This is not a bug: it’s a result of the fact that most decimal fractions can’t be represented exactly as a float....
The behaviorofround()forfloats can be surprising:forexample,round(2.675,2)gives2.67insteadofthe expected2.68.This is not a bug:it’s a resultofthe fact that most decimal fractions can’t be represented exactlyasa float.See Floating Point Arithmetic:Issues and Limitationsformore information. ...