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#include <math.h>
#include <stdio.h>
//#if 1 //(UGLY_IEEE754_FLOAT32_HACK :-)
/*
static inline float todB_a(const float *x){
return (float)((*(int *)x)&0x7fffffff) * 7.17711438e-7f -764.6161886f;
}
*/
static inline float todB_a(const float *x){
union {
//int32_t i;
int i;
float f;
} ix;
ix.f = *x;
ix.i = ix.i&0x7fffffff;
return (float)(ix.i * 7.17711438e-7f -764.6161886f);
}
//#else
static inline float todB_a2(const float *x){
return (*(x)==0?-400.f:logf(*(x)**(x))*4.34294480f);
}
//#endif
int main() {
float f;
for(f=1.f;f<100000000.f;f*=1.2f)
printf("%f\t%f\n", todB_a(&f), todB_a2(&f));
return 0;
}
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