bcb中有四舍五入的函数吗

[qlsoftzj]

bcb中有四舍五入的函数吗？

[ljianq]

RoundTo();

[7rainbow]

include <Math.hpp>

double n=1.234;

n=RoundTo(n, -2)//取小位后二位 1.23
n=RoundTo(n, -1)//取小位后一位 1.2

[我不懂电脑]

Rounds a floating-point value to a specified digit or power of ten using “Banker’s rounding”.

Unit

Math

Category

Arithmetic routines

typedef Word TRoundToRange;
extern PACKAGE double __fastcall RoundTo(const double AValue, const TRoundToRange ADigit);

Description

Call RoundTo to round AValue to a specified power of ten.

AValue is the value to round.

ADigit indicates the power of ten to which you want AValue rounded. It can be any value from –37 to 37 (inclusive).

RoundTo uses “Banker’s Rounding” to determine how to round values that are exactly midway between the two values that have the desired number of significant digits. This method rounds to an even number in the case that AValue is not nearer to either value.

The following examples illustrate the use of RoundTo:

Expression Value

RoundTo(1234567, 3) 1234000
RoundTo(1.234, -2) 1.23
RoundTo(1.235, -2) 1.24
RoundTo(1.245, -2) 1.24

Note: The behavior of RoundTo can be affected by the Set8087CW procedure or SetRoundMode function.

[borland_boy]

n=RoundTo(a, b)

//a 要转换的变量
//b 取几位小数注意是负数

[Atomictry]

哈哈，给参数加上0.5,你就知道怎么搞了。

[GeoPhoenix]

float b = 0.6;
int a = (int) (b+0.5);

[Behard]

float fTemp = 1.4;
int iTemp = fTemp+ 0.5;
ShowMessage ( IntToStr(iTemp) );

fTemp = 1.6;
iTemp = fTemp+ 0.5;
ShowMessage ( IntToStr(iTemp) );

[yjy1001]

RoundTo() ;//四舍 5入

TrunC();//向下取整

具体 使用 请查看帮助 都有例子的