Add Conversion functions for Spectrum Waveform (#23)

* add converters for spectrum waveform

* shorten test name

* use from_array_1d

* PR feedback

Author: hellovolcano

packages/ni.protobuf.types/src/ni/protobuf/types/waveform_conversion.py

@@ -14,15 +14,17 @@
     ExtendedPropertyDictionary,
     ExtendedPropertyValue,
     NoneScaleMode,
+    Spectrum,
     Timing,
 )
 
 from ni.protobuf.types.precision_timestamp_conversion import (
-    bintime_datetime_to_protobuf,
     bintime_datetime_from_protobuf,
+    bintime_datetime_to_protobuf,
 )
 from ni.protobuf.types.waveform_pb2 import (
     DoubleAnalogWaveform,
+    DoubleSpectrum,
     WaveformAttributeValue,
 )
 
@@ -82,20 +84,45 @@ def float64_analog_waveform_from_protobuf(
             raise ValueError("Could not determine the datatype of 'attribute'.")
         extended_properties[key] = getattr(value, attr_type)
 
-    data_array = np.array(message.y_data)
-    return AnalogWaveform(
-        sample_count=data_array.size,
+    return AnalogWaveform.from_array_1d(
+        message.y_data,
         dtype=np.float64,
-        raw_data=data_array,
-        start_index=0,
-        capacity=data_array.size,
         extended_properties=extended_properties,
-        copy_extended_properties=True,
         timing=timing,
         scale_mode=NoneScaleMode(),
     )
 
 
+def float64_spectrum_to_protobuf(value: Spectrum[np.float64], /) -> DoubleSpectrum:
+    """Convert the Python Spectrum to a protobuf DoubleSpectrum."""
+    attributes = _extended_properties_to_attributes(value.extended_properties)
+
+    return DoubleSpectrum(
+        start_frequency=value.start_frequency,
+        frequency_increment=value.frequency_increment,
+        data=value.data,
+        attributes=attributes,
+    )
+
+
+def float64_spectrum_from_protobuf(message: DoubleSpectrum, /) -> Spectrum[np.float64]:
+    """Convert the protobuf DoubleSpectrum to a Python Spectrum."""
+    extended_properties = {}
+    for key, value in message.attributes.items():
+        attr_type = value.WhichOneof("attribute")
+        if attr_type is None:
+            raise ValueError("Could not determine the datatype of 'attribute'.")
+        extended_properties[key] = getattr(value, attr_type)
+
+    return Spectrum.from_array_1d(
+        message.data,
+        dtype=np.float64,
+        start_frequency=message.start_frequency,
+        frequency_increment=message.frequency_increment,
+        extended_properties=extended_properties,
+    )
+
+
 def _extended_properties_to_attributes(
     extended_properties: ExtendedPropertyDictionary,
 ) -> Mapping[str, WaveformAttributeValue]:

packages/ni.protobuf.types/tests/unit/test_waveform_conversion.py

@@ -2,15 +2,26 @@
 
 import numpy
 from nitypes.bintime import DateTime
-from nitypes.waveform import AnalogWaveform, NoneScaleMode, SampleIntervalMode, Timing
+from nitypes.waveform import (
+    AnalogWaveform,
+    NoneScaleMode,
+    SampleIntervalMode,
+    Spectrum,
+    Timing,
+)
 
-from ni.protobuf.types.precision_timestamp_conversion import bintime_datetime_to_protobuf
+from ni.protobuf.types.precision_timestamp_conversion import (
+    bintime_datetime_to_protobuf,
+)
 from ni.protobuf.types.waveform_conversion import (
-    float64_analog_waveform_to_protobuf,
     float64_analog_waveform_from_protobuf,
+    float64_analog_waveform_to_protobuf,
+    float64_spectrum_from_protobuf,
+    float64_spectrum_to_protobuf,
 )
 from ni.protobuf.types.waveform_pb2 import (
     DoubleAnalogWaveform,
+    DoubleSpectrum,
     WaveformAttributeValue,
 )
 
@@ -139,3 +150,80 @@ def test___dbl_analog_wfm_with_timing_no_dt___convert___valid_python_object() ->
     assert analog_waveform.timing.start_time == t0_dt._to_datetime_datetime()
     assert not analog_waveform.timing.has_sample_interval
     assert analog_waveform.timing.sample_interval_mode == SampleIntervalMode.NONE
+
+
+# ========================================================
+# Spectrum to DoubleSpectrum
+# ========================================================
+def test___default_spectrum___convert___valid_protobuf() -> None:
+    spectrum = Spectrum()
+
+    dbl_spectrum = float64_spectrum_to_protobuf(spectrum)
+
+    assert not dbl_spectrum.attributes
+    assert spectrum.start_frequency == 0.0
+    assert spectrum.frequency_increment == 0.0
+    assert list(dbl_spectrum.data) == []
+
+
+def test___spectrum_with_data___convert___valid_protobuf() -> None:
+    spectrum = Spectrum.from_array_1d(numpy.array([1.0, 2.0, 3.0]))
+    spectrum.start_frequency = 100.0
+    spectrum.frequency_increment = 10.0
+
+    dbl_spectrum = float64_spectrum_to_protobuf(spectrum)
+
+    assert list(dbl_spectrum.data) == [1.0, 2.0, 3.0]
+    assert dbl_spectrum.start_frequency == 100.0
+    assert dbl_spectrum.frequency_increment == 10.0
+
+
+def test___spectrum_with_extended_properties___convert___valid_protobuf() -> None:
+    spectrum = Spectrum()
+    spectrum.channel_name = "Dev1/ai0"
+    spectrum.unit_description = "Volts"
+
+    dbl_spectrum = float64_spectrum_to_protobuf(spectrum)
+
+    assert dbl_spectrum.attributes["NI_ChannelName"].string_value == "Dev1/ai0"
+    assert dbl_spectrum.attributes["NI_UnitDescription"].string_value == "Volts"
+
+
+# ========================================================
+# DoubleSpectrum to Spectrum
+# ========================================================
+def test___default_dbl_spectrum___convert___valid_python_object() -> None:
+    dbl_spectrum = DoubleSpectrum()
+
+    spectrum = float64_spectrum_from_protobuf(dbl_spectrum)
+
+    assert not spectrum.extended_properties
+    assert spectrum.start_frequency == 0.0
+    assert spectrum.frequency_increment == 0.0
+    assert spectrum.sample_count == 0
+    assert spectrum.data.size == 0
+
+
+def test___dbl_spectrum_with_data___convert___valid_python_object() -> None:
+    dbl_spectrum = DoubleSpectrum(
+        data=[1.0, 2.0, 3.0], start_frequency=100.0, frequency_increment=10.0
+    )
+
+    spectrum = float64_spectrum_from_protobuf(dbl_spectrum)
+
+    assert list(spectrum.data) == [1.0, 2.0, 3.0]
+    assert spectrum.start_frequency == 100.0
+    assert spectrum.frequency_increment == 10.0
+
+
+def test___dbl_spectrum_with_attributes___convert___valid_python_object() -> None:
+    attributes = {
+        "NI_ChannelName": WaveformAttributeValue(string_value="Dev1/ai0"),
+        "NI_UnitDescription": WaveformAttributeValue(string_value="Volts"),
+    }
+    dbl_spectrum = DoubleSpectrum(attributes=attributes)
+
+    spectrum = float64_spectrum_from_protobuf(dbl_spectrum)
+
+    assert spectrum.channel_name == "Dev1/ai0"
+    assert spectrum.unit_description == "Volts"