&domain
The domain of this axis (e.g. "time" or "frequency").
&unit
The unit of this axis (e.g. "ms" or "kHz").
&refValue
The value based upon which the values of this axis have been calculated, if applicable.
&class
The "class" of this axis, showing how its values have been calculated (e.g. "lin" (linear) or "dB").
See AAxis for additional member variables.