Workdocumentation 2018-08-18

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// rvp6LittleEndian converts the raw two byte tuple of little endian encoded composite products
// to radar video processor values (rvp-6). NaN may be returned when the no-data flag is set.
func (c *Composite) rvp6LittleEndian(tuple [2]byte) float32 {
	var value int = 0x0F & int(tuple[1])
	value = (value << 8) + int(tuple[0])

	if tuple[1]&(1<<5) != 0 { // error code: no-data
		return NaN
	}

	if tuple[1]&(1<<6) != 0 { // flag: negative value
		value *= -1
	}

	conv := c.rvp6Raw(value) // set decimal point

	// little endian encoded formats are also used for mm/h
	if c.DataUnit != Unit_dBZ {
		return conv
	}

	// Even though this format supports negative values and custom
	// precision they do not make use of this and we still have to subtract
	// the bias and scale it (RADVOR FX, dBZ)
	return toDBZ(conv)
}

// rvp6Raw converts the raw value to radar video processor values (rvp-6) by applying the
// products precision field.
func (c *Composite) rvp6Raw(value int) float32 {
	return float32(value) * float32(math.Pow10(c.precision))
}