.. index:: amplifier test, amplifier data structure, compression point

Amplifier test data
===================

``AmplifierTest`` uses one general raw and processed container::

   raw = history.rawData[description]
   result = history.processedData[description]

Raw data
--------

A dataset has three parallel channels: ``sg_pout``, ``amp_pin``, and
``amp_pout``. Their path is::

   raw[channel][frequency][repr(generator_level)][sample]

``frequency`` is a numeric frequency value in Hz. For historical
compatibility, the generator level is the string representation of a power
quantity, for example ``"Quantity(W, 0.001)"``. Applications should not
interpret this key numerically; use the stored ``value`` or
:func:`mpylab.env.Measure.parse_quantity`.

Each list entry contains ``value``, ``pfwd``, and ``pbwd``:

* In ``sg_pout``, ``value`` is the configured generator level.
* In ``amp_pin``, ``value`` is the path-corrected amplifier input power.
* In ``amp_pout``, ``value`` is the path-corrected amplifier output power.

All three values are power quantities. In the ``rack`` setup, ``pfwd`` and
``pbwd`` hold raw values from the two rack power meters. In the ``direct``
setup, both are ``None`` and the entry adds ``pm_out`` with the raw reading of
the directly connected power meter. Compare setups using ``value``, not the
setup-specific raw channels.

Processed data
--------------

``GetGainAndCompression`` replaces ``processedData[description]`` with five
frequency tables:

.. list-table:: Evaluated channels
   :header-rows: 1
   :widths: 35 25 40

   * - Key
     - Path
     - Content
   * - ``gain``
     - ``[frequency][sample]``
     - Power gain as a dimensionless quantity.
   * - ``input_compression_1dB``
     - ``[frequency][sample]``
     - Input power at the 1 dB compression point.
   * - ``input_compression_3dB``
     - ``[frequency][sample]``
     - Input power at the 3 dB compression point.
   * - ``output_compression_1dB``
     - ``[frequency][sample]``
     - Output power at the 1 dB compression point.
   * - ``output_compression_3dB``
     - ``[frequency][sample]``
     - Output power at the 3 dB compression point.

Compression values are power quantities or ``None`` when the respective point
cannot be found in the measured data. Every frequency channel contains lists
because multiple repetitions per generator level can be evaluated. One index
identifies the same repetition across all five channels.

``OutputIniFile`` exports the ``S21``, ``MAXIN``, ``C1DB``, and ``C3DB``
channels from these results. The INI is a derived device configuration and
does not replace the measurement history with raw data and both compression
directions.