DP44/docs/ai/DTS Viewer/DTS.Viewer.Modules/DTS.Viewer.Graph/Model.md

source_files, generated_at, model, schema_version, sha256

source_files	generated_at	model	schema_version	sha256
DTS Viewer/DTS.Viewer.Modules/DTS.Viewer.Graph/Model/TestDataSeries.cs DTS Viewer/DTS.Viewer.Modules/DTS.Viewer.Graph/Model/TestDataSeriesModel.cs	2026-04-17T15:56:35.752282+00:00	zai-org/GLM-5-FP8	1	2fa01244d764d6f0

Documentation: DTS.Viewer.Graph Module - Test Data Series

1. Purpose

This module provides the data model and factory logic for rendering test channel data on graphs within the DTS Viewer application. TestDataSeries serves as the serializable, property-change-notifying data transfer object that holds channel metadata, time/frequency domain data, and computed statistics. TestDataSeriesModel acts as the factory that transforms raw ITestChannel binary data into TestDataSeries instances, handling time-domain, FFT, and PSD (Power Spectral Density) transformations with optional filtering and windowing.

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2. Public Interface

TestDataSeries Class

Namespace: DTS.Viewer.Graph.Model
Inherits: Common.Base.BasePropertyChanged
Implements: ITestDataSeries

Properties

Property	Type	Description
HIC	bool	Indicates if Head Injury Criteria data is present.
HICValue	string	Formatted HIC value.
T1Time / T2Time	string	T1/T2 timestamp strings for HIC calculations.
TestGroup	string	Test group identifier.
TestId	string	Unique test identifier.
TestSetupName	string	Name of the test setup configuration.
ChannelId	string	Channel identifier.
Xvalue	double[]	X-axis data array (time or frequency values).
Yvalue	double[]	Y-axis data array (amplitude values).
GraphColor	Brush	WPF brush for graph rendering. Getter creates new SolidColorBrush from internal byte[].
HardwareChannel	string	Hardware channel name.
Bridge	string	Bridge type identifier.
SWAAF	string	Software anti-aliasing filter setting.
HWAAF	string	Hardware anti-aliasing filter rate.
SampleRate	string	Sample rate in Hz.
RecordingMode	string	Recording mode description.
ISOCode / ISOChannelName	string	ISO channel identification.
UserCode / UserChannelName	string	User-defined channel identification.
ChannelName	string	Display channel name.
Description	string	Channel description.
SensorSN	string	Sensor serial number.
SensorSNDisplay	string	Returns Strings.Table_NA if sensor is test-specific embedded, otherwise returns SensorSN.
EngineeringUnits	string	Engineering units string.
Excitation	string	Excitation voltage.
Polarity	string	Sensor polarity.
MinY / MaxY / AvgY / StdDevY	string	Statistical values, default to Strings.Table_NA.
PeakMagnitude	double	Peak magnitude of frequencies (valid only when FFT is true).
PeakFrequency	double	Frequency of highest magnitude (valid only when FFT is true).
GRMS	double	Root-mean-squared acceleration (calculated in PSD results).
FFT	bool	Indicates whether series is FFT-transformed data.
T0EUValue	string	T0 value regardless of units.
IsSaved	bool	Get-only property (purpose unclear from source).

Methods

public void SetStatsFromYValues()

Sets AvgY, StdDevY, MinY, MaxY, T0EUValue using internal Yvalue array. Formats using "G5" format string.

public void SetStatsFromYValues(double[] values)

Overload that accepts an external double[] array. Handles null/empty arrays by setting all stats to NaN (displayed as Strings.Table_NA).

public void SetStatsFromChannel(ITestChannel channel)

Sets statistics from pre-calculated values on an ITestChannel instance (channel.MinY, channel.MaxY, channel.AveY, channel.StdDevY, channel.T0Value).

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TestDataSeriesModel Class

Namespace: DTS.Viewer.Graph
Implements: IBaseModel

Properties

Property	Type	Description
Parent	IGraphViewModel	Parent view model reference.
_eventAggregator	IEventAggregator	Prism event aggregator for publishing progress events.
ErrorMessage	string	Error message with property change notification.
IsSaved	bool	Get-only property (purpose unclear from source).

Methods

public Task<ITestDataSeries> GetTestDataAsync(ITestChannel channel, IChartOptionsModel chartOptions, bool bVolts, IPSDReportSettingsModel psdSettings = null)

Async wrapper that calls synchronous GetTestData. Returns a single ITestDataSeries.

public Task<List<ITestDataSeries>> GetTestDataAsync(List<ITestChannel> channels, IChartOptionsModel chartOptions, bool bVolts, IPSDReportSettingsModel psdSettings = null)

Async wrapper for batch channel processing. If psdSettings.ShowEnvelope is true, appends an envelope channel to results.

public List<ITestDataSeries> GetTestData(List<ITestChannel> channels, IChartOptionsModel chartOptions, bool bVolts, IPSDReportSettingsModel psdSettings = null)

Synchronous batch processing. Catches OutOfDataException and re-throws with sample index context.

public ITestDataSeries GetTestData(ITestChannel channel, IChartOptionsModel chartOptions, bool bVolts, IPSDReportSettingsModel psdSettings = null)

Entry point for single channel processing, delegates to AddTestChannelToChart.

public TestDataSeries AddTestChannelToChart(ITestChannel channel, IChartOptionsModel chartOptions, bool bVolts, IPSDReportSettingsModel psdSettings = null)

Primary factory method. Reads binary channel data via Serialization.SliceRaw.File.Reader.ReadChannelsBinaryData, then:

• For FFT mode (chartOptions.UnitType == FFT and no PSD settings): Sets FFT=true, populates PeakFrequency, PeakMagnitude, Xvalue, Yvalue.
• For regular time-domain: Calculates time axis with unit conversion (ms or s), handles HIC data if present, sets stats from channel.
• For PSD mode: Applies data range selection, resizes to power-of-2 length, applies optional low-pass/high-pass filters, computes PSD via FftSharp.Transform.PSD_Welch, calculates GRMS.

Returns null if channel.ErrorMessage is not empty.

private ITestDataSeries GetEnvelopeChannel(List<ITestDataSeries> data)

Creates an envelope channel by taking the maximum Y value at each frequency across all input series. Sets ChannelId and related fields to Strings.EnvelopeUnique.

private double CalculateGRMS(double[] freq, double[] psd)

Calculates Grms using numerical integration of PSD curve. Handles logarithmic slope calculation with special case for N=-1.

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3. Invariants

1. Array Initialization: Xvalue and Yvalue are initialized to empty arrays (new double[0]), never null.
2. GraphColor Thread Safety: GraphColor getter always creates a new SolidColorBrush instance; internal storage is byte[] _graphColorARGB to ensure thread safety (per comment referencing issue 34455).
3. FFT/PSD Filter Bypass: When chartOptions.UnitType is FFT or PSD, channel.SoftwareFilter is forcibly set to "none" before reading data.
4. Statistics Format: All statistical string properties use "G5" format specifier via STAT_FORMAT constant.
5. PSD Data Length: PSD processing resizes input arrays to the next enclosing power of 2 via Utils.GetEnclosingPower2.
6. Frequency Array First Element: In PSD processing, freq[0] is explicitly set to 1 after calculation.
7. SensorSNDisplay Logic: Returns Strings.Table_NA when SensorConstants.IsTestSpecificEmbedded(SensorSN) returns true.

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4. Dependencies

Imports (What this module depends on):

TestDataSeries.cs:

• DTS.Common.Enums.Sensors - SensorConstants for embedded sensor detection
• DTS.Common.Interface - ITestDataSeries interface
• DTS.Common.Strings - Localized string constants
• System.Windows.Media - WPF `Brush