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@cloudwu
Last active January 30, 2023 04:29
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fast IEEE 754 float random
#include <stdint.h>
#include <stdlib.h>
// assert(RAND_MAX >= 0x7fff)
float
random_0_to_1() {
union {
uint32_t d;
float f;
} u;
u.d = (((uint32_t)rand() & 0x7fff) << 8) | 0x3f800000;
return u.f - 1.0f;
}
float
random_minus1_to_1() {
union {
uint32_t d;
float f;
} u;
u.d = (((uint32_t)rand() & 0x7fff) << 8) | 0x40000000;
return u.f - 3.0f;
}
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