pack and unpack a range of a float into a limit...

为什么80%的码农都做不了架构师？>>>   

Code functions that pack and unpack a range of a float into a limited number of bits.

unsigned int pack_float(float val, float minVal, float maxVal, int bits);

float unpack_float(unsigned int val, float minVal, float maxVal, int bits);

#include <iostream>
#include <cassert>

using namespace std;

// Code functions to pack and unpack a range of a float into a limited 
// number of bits:
unsigned int pack_float (float val, float minVal, float maxVal, int bits);
float unpack_float(unsigned int val, float minVal, float maxVal, int bits);

unsigned int pack_float(float val, float minVal, float maxVal, int bits)
{
    assert(bits < 32);
    assert(val >= minVal && val < maxVal);
    return (unsigned int)(1U<<bits)*(val-minVal)/(maxVal-minVal);
}

float unpack_float(unsigned int val, float minVal, float maxVal, int bits)
{
    assert(bits < 32);
    assert(val < (1U<<bits));
    return val*(maxVal-minVal)/(1U<<bits)+minVal;
}


int main(int argc, char* argv[])
{
    float val = 1234.4567;
    float minVal = 0.0;
    float maxVal = 6789.0;
    unsigned int packed = pack_float(val, minVal, maxVal, 16);
    float unpacked = unpack_float(packed, minVal, maxVal, 16);
    cout << "pack: " << packed << endl;
    cout << "unpack: " << unpacked << endl;

    return 0;
}

转载于:https://my.oschina.net/qihh/blog/94087