code: func WriteFloat64Lossy(space []byte, val float64) []byte {
  	if val < 0 {
  		space = append(space, '-')
  		val = -val
  	}
  	if val > 0x4ffffff {
  		return WriteFloat64(space, val)
  	}
  	precision := 6
  	exp := uint64(1000000) // 6
  	lval := uint64(val*float64(exp) + 0.5)
  	space = WriteUint64(space, lval / exp)
  	fval := lval % exp
  	if fval == 0 {
  		return space
  	}
  	space = append(space, '.')
  	for p := precision - 1; p > 0 && fval < pow10[p]; p-- {
  		space = append(space, '0')
  	}
  	space = WriteUint64(space, fval)
  	for space[len(space)-1] == '0' {
  		space = space[:len(space) - 1]
  	}
  	return space
  }
docs: // WriteFloat64Lossy write float64 to stream with ONLY 6 digits precision although much much faster