出处：http://blog.csdn.net/delphiwcdj/article/details/6261931
方法1：判断是否溢出，一是使用函数判断，二是与最大最小值比较
#include <cstdio>
#include <cmath>
#include <cfloat>
int main()
{
// double类型
double dval1 = 1.2;
double dval2 = 1.2*pow((double)10,308);
double dval3 = 1.2*pow((double)10,309);
printf("%d/n",_finite(dval1));// 1 未溢出
printf("%d/n",_finite(dval2));// 1
printf("%d/n",_finite(dval3));// 0 溢出
if (dval1 > DBL_MAX || dval1 < DBL_MIN)
printf("overflow/n");
if (dval2 > DBL_MAX || dval2 < DBL_MIN)
printf("overflow/n");
if (dval3 > DBL_MAX || dval3 < DBL_MIN)
printf("overflow/n");
// float类型
float fval1 = 1.2f;
float fval2 = 1.2f*(float)pow((double)10,38);
float fval3 = 1.2f*(float)pow((double)10,39);
printf("%d/n",_finite(fval1));// 1 未溢出
printf("%d/n",_finite(fval2));// 1
printf("%d/n",_finite(fval3));// 0 溢出
if (fval1 > FLT_MAX || fval1 < FLT_MIN)
printf("overflow/n");
if (fval2 > FLT_MAX || fval2 < FLT_MIN)
printf("overflow/n");
if (fval3 > FLT_MAX || fval3 < FLT_MIN)
printf("overflow/n");
return 0;
#include <iostream>
#include <float.h>
using namespace std;
int main()
{
float f = 0.f;
float d = -100.f / f;// -1.#INF000
if (d > FLT_MAX || d < FLT_MIN)
cout<<"error"<<endl;
float x = 1e100;
if (x > FLT_MAX || x < FLT_MIN)
cout<<"error"<<endl;
return 0;
}
方法2：捕获浮点数溢出异常
#include <cstdio>
#include <cmath>
#include <cfloat>
#include <fpieee.h>
#include <excpt.h>
#include <float.h>
int fpieee_handler(_FPIEEE_RECORD *pieee)
{
if (pieee->Cause.Overflow == 1) {// 处理溢出
return EXCEPTION_CONTINUE_EXECUTION;
} else {
return EXCEPTION_EXECUTE_HANDLER;
}
}
int main()
{
__try {
unsigned int u;
unsigned int control_word;
_controlfp_s(&control_word, 0, 0);
u = control_word & (~_EM_OVERFLOW);
_controlfp_s( &control_word, u, _MCW_EM);
// 你的代码
// double类型
double dval3 = 1.2*pow((double)10,309);
printf("%d/n",_finite(dval3));// 0 溢出=> 1
if (dval3 > DBL_MAX || dval3 < DBL_MIN)
printf("overflow/n");
// float类型
float fval3 = 1.2f*(float)pow((double)10,39);
printf("%d/n",_finite(fval3));// 0 溢出=> 1
if (fval3 > FLT_MAX || fval3 < FLT_MIN)
printf("overflow/n");
}
__except (_fpieee_flt(GetExceptionCode(),
GetExceptionInformation(),
fpieee_handler)){
}
}
float.h文件中定义的一些常量：
...
#define DBL_DIG 15 /* # of decimal digits of precision */
#define DBL_EPSILON 2.2204460492503131e-016 /* smallest such that 1.0+DBL_EPSILON != 1.0 */
#define DBL_MANT_DIG 53 /* # of bits in mantissa */
#define DBL_MAX 1.7976931348623158e+308 /* max value */
#define DBL_MAX_10_EXP 308 /* max decimal exponent */
#define DBL_MAX_EXP 1024 /* max binary exponent */
#define DBL_MIN 2.2250738585072014e-308 /* min positive value */
#define DBL_MIN_10_EXP (-307) /* min decimal exponent */
#define DBL_MIN_EXP (-1021) /* min binary exponent */
#define _DBL_RADIX 2 /* exponent radix */
#define _DBL_ROUNDS 1 /* addition rounding: near */
#define FLT_DIG 6 /* # of decimal digits of precision */
#define FLT_EPSILON 1.192092896e-07F /* smallest such that 1.0+FLT_EPSILON != 1.0 */
#define FLT_GUARD 0
#define FLT_MANT_DIG 24 /* # of bits in mantissa */
#define FLT_MAX 3.402823466e+38F /* max value */
#define FLT_MAX_10_EXP 38 /* max decimal exponent */
#define FLT_MAX_EXP 128 /* max binary exponent */
#define FLT_MIN 1.175494351e-38F /* min positive value */
#define FLT_MIN_10_EXP (-37) /* min decimal exponent */
#define FLT_MIN_EXP (-125) /* min binary exponent */
#define FLT_NORMALIZE 0
#define FLT_RADIX 2 /* exponent radix */
#define FLT_ROUNDS 1 /* addition rounding: near */
...