floating point - How is this in Q10 format? -

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i've read else's code , claimed answer in q10 format. can't figure out how in q10. here code:

// convert x , y in such manner ratio of x y // produce value in q10 format cnt = 0; bitmask = 0x80000000;  while((cnt < 10) && !(bitmask & x)) {   x <<= 1;   cnt++; } y >>= (10 - cnt);  // calculate slope if (0 == x)   slope = 0xffffffff; else   slope = ((uint32)x)/(uint32)y;

any appreciated

i'll assume q10 mean value has 10 bits representing fractional portion of fixed point value. code in question produce q10 value if x , y inputs have same number of fractional bits (i.e., same "q" value). input x shifted left 10 bits, increases q value of x number of bits shifted. if x shifted less 10 bits (to avoid overflow) y shifted right remaining bits (decreasing q value of y) difference between q values of x , y 10. slope calculated x/y. when divide fixed point values q value of result equal q value of numerator minus q value of denominator. slope q10 because q value of x , y differ 10.


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