DP44/docs/ai/Common/DTS.Common.Serialization/Control/Event/Module/Channel.md

source_files, generated_at, model, schema_version, sha256

source_files	generated_at	model	schema_version	sha256
Common/DTS.Common.Serialization/Control/Event/Module/Channel/DataValues.cs Common/DTS.Common.Serialization/Control/Event/Module/Channel/ReviewableAttribute.NotApplicableException.cs Common/DTS.Common.Serialization/Control/Event/Module/Channel/Filter.cs Common/DTS.Common.Serialization/Control/Event/Module/Channel/ChannelDefaultSaeJ211Filter.cs Common/DTS.Common.Serialization/Control/Event/Module/Channel/CalculatedChannel.cs Common/DTS.Common.Serialization/Control/Event/Module/Channel/SaeJ211Filter.cs	2026-04-17T15:34:47.007360+00:00	zai-org/GLM-5-FP8	1	ba30fc370955c9dd

DTS.Slice.Control.Event.Module.Channel Documentation

1. Purpose

This module provides the channel-level data structures and filtering mechanisms for the DTS Slice Control Event system. It defines classes for storing channel data values (with optional memory-mapped file support for large datasets), implements SAE J211-compliant digital filters for signal processing, and provides a hierarchy of calculated channel types for derived data operations such as integration, differentiation, FFT analysis, and vector mathematics. The module exists to support data acquisition and analysis workflows within the larger DTS Slice framework.

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2. Public Interface

Event.Module.Channel.DataValues

A class representing a channel's data, inheriting from Exceptional.

Constructors:

• DataValues() — Initializes with memory-mapped file support enabled by default.
• DataValues(bool useMemoryMappedFile) — Initializes with explicit control over memory-mapped file usage.

Properties:

• bool UseMemoryMappedFile { get; set; } — Controls whether the class uses memory-mapped files instead of in-memory lists for data storage.

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Event.Module.Channel.ReviewableAttribute.NotApplicableException

An exception class for attempts to use a channel attribute that is not applicable to the associated channel. Inherits from ApplicationException.

Constructors:

• NotApplicableException()
• NotApplicableException(string msg)
• NotApplicableException(string msg, System.Exception innerEx)

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Event.Module.Channel.Filter (Abstract)

Abstract base class for channel filters. Implements Exceptional and IFilter.

Abstract Properties:

• string Name { get; } — Descriptive designation for the filter.
• bool IsCfc { get; } — Indicates whether the filter corresponds to a CFC (Channel Filter Class) value.
• ChannelFilter Type { get; } — The ChannelFilter designation for this filter.
• double CutoffFrequencyHz { get; } — The cutoff frequency in Hz.

Abstract Methods:

• double[] Apply(Channel input, DataDisplayUnits displayUnits, bool bUseLegacyTDCSoftwareFilterAdjustment) — Applies the filter to a channel.
• double[] Apply(double[] data, double sampleRate, bool bUseLegacyTDCSoftwareFilterAdjustment) — Applies the filter to raw data.
• string ToBaseString() — Returns the base name without decoration (contrast with ToString()).

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Event.Module.Channel.SaeJ211Filter

Concrete implementation of SAE J211-based filters. Inherits from Filter.

Constructors:

• SaeJ211Filter(SaeJ211Filter originalFilter) — Copy constructor.
• SaeJ211Filter(ChannelFilter originalType) — Initializes from a ChannelFilter enum value. Throws Exception if ChannelFilter.AdHoc is passed.
• SaeJ211Filter(double cutoffFrequencyHz) — Initializes an ad hoc filter with a specific cutoff frequency.

Properties:

• override bool IsCfc { get; } — Returns true if the filter is CFC-compliant (not Unfiltered and not AdHoc).
• override ChannelFilter Type { get; } — Returns the best-fitting ChannelFilter value.
• char IsoDescription { get; } — Returns the ISO description character.
• override double CutoffFrequencyHz { get; } — The cutoff frequency.
• ChannelFilter OriginalType { get; } — The original filter type specified at construction.
• override string Name { get; } — The filter name (e.g., "1000Hz" for ad hoc, or the CFC description).

Methods:

• override double[] Apply(Channel channel, DataDisplayUnits displayUnits, bool bUseLegacyTDCSoftwareFilterAdjustment) — Applies the filter to channel data.
• override double[] Apply(double[] data, double sampleRate, bool bUseLegacyTDCSoftwareFilterAdjustment) — Applies the filter to raw data.
• override string ToString() — Returns Name.
• override string ToBaseString() — Returns Name.
• override bool Equals(object obj) — Compares filters by name (case-insensitive).
• override int GetHashCode() — Returns hash based on lowercase name.
• static Filter Parse(string serialization) — Creates a filter from a string representation.

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Event.Module.Channel.DefaultSaeJ211Filter

A default wrapper for SAE J211 filters. Inherits from SaeJ211Filter.

Constructors:

• DefaultSaeJ211Filter(SaeJ211Filter filter) — Wraps an existing filter.
• DefaultSaeJ211Filter(ChannelFilter filterType) — Creates a filter from a ChannelFilter type.
• DefaultSaeJ211Filter(double adHocFrequency) — Creates an ad hoc filter with specified frequency.

Properties:

• override string Name { get; } — Returns "Default (" + base.Name + ")".

Methods:

• override string ToBaseString() — Returns base.Name.
• override string ToString() — Returns Name.

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Event.Module.Channel.CalculatedChannel (Abstract)

Abstract base class for calculated/derived channels. Inherits from Channel and implements IEngineeringUnitAware.

Nested Enum:

• Operation — Values: Integral, Derivative, HeadInjuryCriteria, FFT, ImportedCSV, Resultant, TSR, Scale, Offset, Sine, Cosine.

Nested Enum:

• XUnits — Values: msec, sec, Hz, samples.

Properties:

• Operation CalculationType { get; } — The calculation type.
• double[] X { get; } — X-axis values.
• double[] Y { get; } — Y-axis values.
• XUnits XAxis { get; } — X-axis unit type.
• string XUnitsString { get; } — String representation of X units.
• string EngineeringUnits { get; set; } — Y-axis engineering units.
• override bool SupportsADC { get; } — Returns false.
• override bool SupportsEU { get; } — Returns true.
• override bool SupportsmV { get; } — Returns false.
• override double ActualMaxRangeEu { get; } — Returns Y.Max().
• override double ActualMinRangeEu { get; } — Returns Y.Min().
• override double DataHalfRangeValueEu { get; }, DataMaxEu { get; }, DataMinEu { get; }, DataRangeEu { get; } — Statistical properties of Y data.
• override bool IsConfigured { get; set; } — Always true; setter throws NotSupportedException.

Constructor:

• CalculatedChannel(string name, XUnits xAxis, string yAxis, double[] xValues, double[] yValues, Operation calcType, int number, Module parentModule)

Methods that throw NotSupportedException or NotImplementedException:

• override void FromDtsSerializationTestModuleChannel(Serialization.Test.Module.Channel that)
• override void SetPropertyValuesFrom(DASLib.Service.DASChannel dasChannel)
• override void SetPropertyValuesFrom(DASLib.Service.DiagnosticsResult diagResults)
• override Serialization.Test.Module.Channel ToDtsSerializationTestModuleChannel(Serialization.Test.Module parentModule)
• override double ActualMaxRangeMv { get; }
• override double ActualMinRangeMv { get; }
• override double SensorCapacityEU { get; }
• override double DesiredRangeEU { get; }
• override List<double> GetUnfilteredDataMV()

Methods:

• override List<double> GetUnfilteredDataEu() — Returns a copy of Y values.
• override string ToString() — Returns ChannelDescriptionString or "N/A".

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Concrete Calculated Channel Types

All inherit from CalculatedChannel and have identical constructor signatures:

• FFTCalculatedChannel — Additional property: double PeakFrequency { get; }. Constructor includes extra double peakFrequency parameter.
• IntegralCalculatedChannel
• DerivativeCalculatedChannel
• ScaleCalculatedChannel
• OffsetCalculatedChannel
• ResultantCalculatedChannel
• AdditiveVectorCalculatedChannel
• SineCalculatedChannel
• CosineCalculatedChannel

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3. Invariants

1. Filter Type Consistency: SaeJ211Filter.Type will never return ChannelFilter.AdHoc if the cutoff frequency exactly matches a CFC value; it will return the matching CFC type instead.

2. CFC Compliance: SaeJ211Filter.IsCfc returns true only when Type is neither Unfiltered nor AdHoc.

3. Filter Equality: Two SaeJ211Filter instances are considered equal if their Name properties match case-insensitively. Consequently, GetHashCode() is based on the lowercase name.

4. Calculated Channel Data Immutability: X and Y data arrays in CalculatedChannel are stored in readonly List<double> fields and exposed as copies via ToArray().

5. Calculated Channel Capabilities: All CalculatedChannel derivatives have SupportsADC = false, SupportsEU = true, and SupportsmV = false.

6. Parse Round-Trip: SaeJ211Filter.Parse() can parse filter names produced by ToString(); unrecognized strings return an Unfiltered filter.

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4. Dependencies

This module depends on:

• DTS.Common.Utilities — Provides Exceptional base class, Exception, Property<T>, APILogger.
• DTS.Common.Utilities.DotNetProgrammingConstructs — Provides Property<T>.
• DTS.Common.Utilities.SaeJ211 — Provides FilterUtility, CfcValueAttributeCoder, DescriptionAttributeCoder<T>, IsoDescriptionAttributeCoder.
• DTS.Common.Utilities.Logging — Provides APILogger.
• DTS.Common.DAS.Concepts.DAS.Channel — Provides ChannelFilter, IFilter, IEngineeringUnitAware.
• DTS.Slice.Control.DAS.Channel — Referenced in Filter.cs.
• DASLib.Service — Provides DASChannel, DiagnosticsResult (used in CalculatedChannel).
• System namespaces — Standard .NET types.

What depends on this module:

• Cannot be fully determined from source alone, but the partial class structure (Event.Module.Channel) indicates this is part of a larger DTS.Slice.Control namespace hierarchy.

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5. Gotchas

1. Empty Memory-Mapped File Implementation: In DataValues.DataValues(bool useMemoryMappedFile), the if (UseMemoryMappedFile) block is empty. The feature appears to be a stub or incomplete implementation.

2. Legacy TDC Filter Adjustment: The Apply methods on filters accept a bool bUseLegacyTDCSoftwareFilterAdjustment parameter (referenced as "8747" in comments) that adjusts filtered data by one sample to match legacy TDC behavior. This may produce unexpected results if not understood.

3. NotSupportedException on CalculatedChannel: Many methods on CalculatedChannel throw NotSupportedException or NotImplementedException. These include serialization methods, mV-related properties, and some range properties. Callers must handle these exceptions.

4. AdHoc Filter Construction Restriction: SaeJ211Filter(ChannelFilter originalType) throws an Exception if passed ChannelFilter.AdHoc. Use the SaeJ211Filter(double cutoffFrequencyHz) constructor instead.

5. Large Data Handling in Filter.Apply: When filtering ADC data, the method checks for ILargeDataAware.IsDataArraySized and throws DataTooBigForArrayException if data is too large. This is a runtime consideration for large datasets.

6. Commented-Out Code: Significant blocks of code are commented out in CalculatedChannel.cs, including the entire HICCalculatedChannel class and InitializeReviewableAttributes implementations. This suggests incomplete features or tech debt.

7. Filter Name Ambiguity: DefaultSaeJ211Filter.Name returns "Default (" + base.Name + ")", while ToBaseString() returns just base.Name. The ToString() returns the decorated name. Use ToBaseString() when the undecorated name is needed.