#include?“stdio.h“
#include?“math.h“
float?tanArray[89]?=?{
0.0174551??????0.0349208??????0.0524078??????0.0699268??????0.0874887??????0.105104???????0.122785???????0.140541???????0.158384???????0.176327

0.19438????????0.212557???????0.230868???????0.249328???????0.267949???????0.286745???????0.305731???????0.32492????????0.344328???????0.36397

0.383864???????0.404026???????0.424475???????0.445229???????0.466308???????0.487733???????0.509525???????0.531709???????0.554309???????0.57735

0.600861???????0.624869???????0.649408???????0.674509???????0.700208???????0.726543???????0.753554???????0.781286???????0.809784???????0.8391

0.869287???????0.900404???????0.932515???????0.965689???????1??????????????1.03553????????1.07237????????1.11061????????1.15037????????1.19175

1.2349?????????1.27994????????1.32704????????1.37638????????1.42815????????1.48256????????1.53986????????1.60033????????1.66428????????1.73205

1.80405????????1.88073????????1.96261????????2.0503?????????2.14451????????2.24604????????2.35585????????2.47509????????2.60509????????2.74748

2.90421????????3.07768????????3.27085????????3.48741????????3.73205????????4.01078????????4.33148????????4.70463????????5.14455????????5.67128

6.31375????????7.11537????????8.14434????????9.51436????????11.43??????????14.3007????????19.0811????????28.6362????????57.2899?????????
};


unsigned?char?getangle（double?data）
{
	unsigned?char?index?=?89;
	unsigned?char?mid?=?45;
	unsigned?char?begin?=?0;
	unsigned?char?end?=?89;
	unsigned?char?right?=?0;
	
	if（data>tanArray[88]）
	{
		return?89;
	}
	
	if（data	{
		return?1;
	}
	
	while（1）
	{
		index?=?（（end?-?begin）/2）+begin;//第二次循環是23

		if（data>tanArray[index]）
		{
			right?=?1;
			begin?=?index;
			if（data>tanArray[index]&&data			{
				return?（data-tanArray[index]）>tanArray[index+1]-data?（index+1）:index;
			}
		}
		else
		{
			right?=?0;
			end?=?index;
			if（data>tanArray[index-1]&&data			{
				return?（data-tanArray[index-1]）>tanArray[index]-data?index:（index-1）;
			}
		}??
		
		if（end-begin<1）
		{
			return?（data-tanArray[begin]）>tanArray[end]-data?end:begin;
		}
	}
	
}

/////找到一個位置，放下這個數，能夠讓它即大于前面又小于后面

void?main（）
{
	unsigned?char?data??=??getangle（0.4）;
	printf（“%d“data）;
}

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----

?????文件??????15562??2005-04-27?01:30??atan_tab.c

-----------?---------??----------?-----??----

????????????????15562????????????????????1