对于图像级别来讲，precision怎么计算

正例类别码老仔：那些用户感兴趣的类别含枝，其条类别为负例类别。 recall value是查全率(r)，查全率是被正确分类的正例数量除以测试集中实际的正例数量。 相应的还有查准率（precision）。查准率(p)是被正确分类的正例数量除以分类为正例的迟汪数量。

#include <stdio.h>

#include <string.h>

typedef unsigned char UCHAR

typedef unsigned short USHORT

#define SIZE128 //一个大整数用个字节保存，最多表示位大整数

#define SIZE_10 2 * SIZE

typedef struct BigNum //大整数结构

{

UCHAR data[SIZE] //空间为(SIZE * sizeof(UCHAR))，就是SIZE个字节

}BigNum

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

#ifndef _BIGNUM_H_

#define _BIGNUM_H_

UCHAR atox(char ch) //将一个十六进制的字符(4位)转位数字，转换失败返回xff

BigNum Init(char* str) //初始化大整数，str为十六进制字符卖睁串

int GetByte(BigNum bignum) //判断有多少个字节不为

BigNum MovByteLetf(BigNum bignum, int n) //左移n个字节

BigNum MovByteRight(BigNum bignum, int n) //右移n个手枝字节

int Cmp(BigNum bignum_a, BigNum bignum_b) //大整数比较大小，>返回，<返回-1，==返回

BigNum Add(BigNum bignum_a, BigNum bignum_b) //大整数加法

BigNum Sub(BigNum bignum_a, BigNum bignum_b) //大整数减法

//BigNum Mul(BigNum bignum_a, UCHAR uchar) //大整数乘中薯岁法UCHAR

BigNum Mul(BigNum bignum_a, BigNum bignum_b) //大整数乘法

BigNum Div(BigNum bignum_a, BigNum bignum_b) //大整数除法

BigNum Mod(BigNum bignum_a, BigNum bignum_b) //大整数模运算

BigNum Pow(BigNum bignum, int n) //大整数乘方运算

void Print_16(BigNum bignum) //打印十六进制大整数

void Print_10(BigNum bignum) //打印十进制大整数

#endif

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

// BigNum.c : 定义控制台应用程序的入口点。

//

UCHAR atox(char ch) //将一个十六进制的字符(4位)转位数字，转换失败返回xff

{

UCHAR res

if (ch >= '0' &&ch <= '9')

{

res = ch - '0'

}

else if (ch >= 'a' &&ch <= 'f')

{

res = ch - 'a' + 10

}

else if (ch >= 'A' &&ch <= 'F')

{

res = ch - 'A' + 10

}

else

{

printf("change error!\n")

return 0xff

}

return res

}

int GetByte(BigNum bignum) //判断有多少个字节不为

{

int ByteOfBigNum = SIZE

while ((bignum.data[ByteOfBigNum - 1] == 0) &&(ByteOfBigNum >0))

{

ByteOfBigNum--

}

return ByteOfBigNum

}

BigNum MovByteLetf(BigNum bignum, int n) //左移n个字节

{

int i

int bignum_len = GetByte(bignum)

for (i = bignum_len - 1i >= 0i--)

{

if (i + n >= SIZE)

{

continue

}

bignum.data[i + n] = bignum.data[i]

}

for (i = n - 1i >= 0i--)

{

bignum.data[i] = 0

}

return bignum

}

BigNum MovByteRight(BigNum bignum, int n) //右移n个字节

{

int i

int bignum_len = GetByte(bignum)

for (i = 0i <bignum_leni++)

{

if (i + n >= SIZE)

{

bignum.data[i] = 0

continue

}

bignum.data[i] = bignum.data[i + n]

}

return bignum

}

BigNum Init(char* str) //初始化大整数，str为十六进制字符串

{

BigNum bignum

int len = (int)strlen(str)

int i

int j = 0

if (len >2 * SIZE)

{

len = 2 * SIZE

}

for (i = len - 1i >0i -= 2)

{

bignum.data[j] = atox(str[i]) + atox(str[i - 1]) * 16

j++

}

if (i == 0)

{

bignum.data[j] = atox(str[i])

j++

}

while (j <SIZE)

{

bignum.data[j] = 0

j++

}

return bignum

}

int Cmp(BigNum bignum_a, BigNum bignum_b) //大整数比较大小，>返回，<返回-1，==返回

{

int bignum_a_len = GetByte(bignum_a)

int bignum_b_len = GetByte(bignum_b)

int max = bignum_a_len >bignum_b_len ? bignum_a_len : bignum_b_len

int i

for (i = max - 1i >= 0i--)

{

if (bignum_a.data[i] >bignum_b.data[i])

{

return 1

}

if (bignum_a.data[i] <bignum_b.data[i])

{

return -1

}

}

return 0

}

BigNum Add(BigNum bignum_a, BigNum bignum_b) //大整数加法

{

BigNum bignum_c

USHORT temp

UCHAR carry = 0

int i

for (i = 0i <SIZEi++)

{

temp = bignum_a.data[i] + bignum_b.data[i] + carry

bignum_c.data[i] = temp &0x00ff

carry = (temp >>8) &0xff

}

return bignum_c

}

BigNum Sub(BigNum bignum_a, BigNum bignum_b) //大整数减法

{

BigNum bignum_c

USHORT temp

UCHAR carry = 0

int i

for (i = 0i <SIZEi++)

{

temp = bignum_a.data[i] - bignum_b.data[i] - carry

bignum_c.data[i] = temp &0x00ff

carry = (temp >>15) &0x01

}

return bignum_c

}

BigNum Mul(BigNum bignum_a, BigNum bignum_b) //大整数乘法

{

BigNum bignum_c = Init("0")

USHORT temp

UCHAR carry

int i, j

for (i = 0i <SIZEi++)

{

carry = 0

for (j = 0j <SIZEj++)

{

temp = bignum_a.data[i] * bignum_b.data[j] + bignum_c.data[j + i] + carry

bignum_c.data[j + i] = temp &0x00ff

carry = (temp >>8) &0xff

}

}

return bignum_c

}

BigNum Div(BigNum bignum_a, BigNum bignum_b) //大整数除法

{

BigNum bignum_c = Init("0")

BigNum B

int bignum_a_len

int bignum_b_len

int bignum_c_len

if (Cmp(bignum_b, bignum_c) == 0)

{

printf("错误！除数为\n")

return bignum_c

}

bignum_a_len = GetByte(bignum_a)

bignum_b_len = GetByte(bignum_b)

bignum_c_len = bignum_a_len - bignum_b_len

while (bignum_c_len >= 0)

{

B = MovByteLetf(bignum_b, bignum_c_len)

while (Cmp(bignum_a, B) != -1)

{

bignum_a = Sub(bignum_a, B)

bignum_c.data[bignum_c_len]++

}

bignum_c_len--

}

return bignum_c

}

BigNum Mod(BigNum bignum_a, BigNum bignum_b) //大整数模运算

{

BigNum bignum_c = Init("0")

BigNum B

int bignum_a_len

int bignum_b_len

int bignum_c_len

if (Cmp(bignum_b, bignum_c) == 0)

{

printf("错误！除数为\n")

return bignum_c

}

bignum_a_len = GetByte(bignum_a)

bignum_b_len = GetByte(bignum_b)

bignum_c_len = bignum_a_len - bignum_b_len

while (bignum_c_len >= 0)

{

B = MovByteLetf(bignum_b, bignum_c_len)

while (Cmp(bignum_a, B) != -1)

{

bignum_a = Sub(bignum_a, B)

}

bignum_c_len--

}

return bignum_a

}

BigNum Pow(BigNum bignum, int n) //大整数乘方运算

{

int i

BigNum bignum_res = Init("1")

for (i = 0i <ni++)

{

bignum_res = Mul(bignum_res, bignum)

}

return bignum_res

}

void Print_16(BigNum bignum) //打印十六进制大整数

{

int i

int nFlag = 0

for (i = SIZE - 1i >= 0i--)

{

if (nFlag == 0 &&bignum.data[i] == 0) //前面是的不打印

{

continue

}

else

{

nFlag++

if (nFlag == 1) //首位的不打印，如x01，只打印

{

printf("%x", bignum.data[i])

}

else //后面的要打印

{

printf("%02x", bignum.data[i])

}

}

}

if (nFlag == 0)

{

printf("0")

}

printf("\n")

}

void Print_10(BigNum bignum) //打印十进制大整数

{

int data_10[SIZE_10]

int i = 0

int j

while (Cmp(bignum, Init("0")) == 1)

{

data_10[i] = (Mod(bignum, Init("a"))).data[0]

bignum = (Div(bignum, Init("a")))

i++

}

for (j = i - 1j >= 0j--)

{

printf("%d", data_10[j])

}

printf("\n")

}

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

void GoldNum(int precision)

{

BigNum b1 = Init("2")

BigNum b2 = Init("3")

BigNum b3 = Init("a")

BigNum temp1

BigNum temp2 = b1

int count = 1000

int i = 0

b3 = Pow(b3, precision)

for(i <counti++)

{

temp1 = b2

b2 = Add(b1, b2)

b1 = temp1

temp1 = Mul(b1, b3)

temp1 = Div(temp1, b2)

if(!Cmp(temp1, temp2))

{

Print_10(temp1)

break

}

temp2 = temp1

}

}

int main()

{

GoldNum(100)

return 0

}

这里面的大数加减乘除是直接用这里面的http://wenku.baidu.com/view/f7d13dd2195f312b3169a5d7.html

我只是写了void GoldNum(int precision)函数，precision参数是精度大小

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