Pi 的单/双/扩展精度浮点表示精确到小数点后多少位？
最佳答案
#include <stdio.h>
#define E_PI 3.1415926535897932384626433832795028841971693993751058209749445923078164062
int main(int argc, char** argv)
{
long double pild = E_PI;
double pid = pild;
float pif = pid;
printf("%s\n%1.80f\n%1.80f\n%1.80Lf\n",
"3.14159265358979323846264338327950288419716939937510582097494459230781640628620899",
pif, pid, pild);
return 0;
}
结果:
[quassnoi #] gcc --version
gcc (GCC) 4.3.2 20081105 (Red Hat 4.3.2-7)
[quassnoi #] ./test
3.14159265358979323846264338327950288419716939937510582097494459230781640628620899
3.14159274101257324218750000000000000000000000000000000000000000000000000000000000
^
3.14159265358979311599796346854418516159057617187500000000000000000000000000000000
^
3.14159265358979311599796346854418516159057617187500000000000000000000000000000000
^
0000000001111111
1234567890123456
关于floating-point - float 的 PI 和精度，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/507819/