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WaveformGroupCount Property

Summary

Gets the number of waveform multiplex groups that are included in the dataset.

Syntax

C#
VB
WinRT C#
C++
public int WaveformGroupCount {get;} 
Public ReadOnly Property WaveformGroupCount As Integer 
public int WaveformGroupCount {get;} 
 get_WaveformGroupCount();  
public: 
property int WaveformGroupCount { 
   int get(); 
} 

Property Value

Value that represents the number of waveform multiplex groups that are included in the dataset.

Remarks

In DICOM, a waveform consists of one or more multiplex groups, each encoded into an item in the "Waveform Sequence" (5400,0100). Use this method to retrieve the number of items under that sequence. Once you know the total number of multiplex groups, call the GetWaveformGroup method to extract a specific group or the DeleteWaveformGroup method to delete it.

Example

This is a comprehensive sample, which shows how to insert a waveform group with one ECG channel into a dataset. The main method is InsertECGCWaveform ,and the rest of the methods are helping methods.All these methods are assumed to be part of the same class. The main method that creates the waveform group and adds it to the dataset

C#
VB
using Leadtools; 
using Leadtools.Dicom; 
 
public void InsertECGCWaveform(DicomDataSet inputDS, short[] samples, int count) 
{ 
 
   // Our new waveform group 
   DicomWaveformGroup ECGWaveformGroup = new DicomWaveformGroup(); 
 
   // Reset the waveform group, we don't  
   // really need to call this!  
   ECGWaveformGroup.Reset(); 
 
   // Set the number of samples per channel. You can call  
   // DicomWaveformGroup.GetNumberOfSamplesPerChannel to get  
   // the number of samples 
   ECGWaveformGroup.SetNumberOfSamplesPerChannel(count); 
 
   // Set the sampling frequency. You can call  
   // DicomWaveformGroup.GetSamplingFrequency to  
   // get the sampling frequency 
   ECGWaveformGroup.SetSamplingFrequency(240.00); 
 
   // Set sample interpretation 
   ECGWaveformGroup.SetSampleInterpretation(DicomWaveformSampleInterpretationType.Signed16BitLinear); 
 
   // Just in case!  
   Debug.Assert(ECGWaveformGroup.GetSampleInterpretation() == DicomWaveformSampleInterpretationType.Signed16BitLinear); 
 
   // No Multiplex Group Time Offset 
   // You can call DicomWaveformGroup.GetMultiplexGroupTimeOffset  
   // to get the time offset 
   ECGWaveformGroup.SetMultiplexGroupTimeOffset(false, 0.0); 
 
   // No Trigger Time Offset 
   // You can call DicomWaveformGroup.GetTriggerTimeOffset  
   // to get the trigger time offset 
   ECGWaveformGroup.SetTriggerTimeOffset(false, 0.0); 
 
   // No Trigger Sample Position 
   // You can call DicomWaveformGroup.GetTriggerSamplePosition 
   // to get the trigger sample position 
   ECGWaveformGroup.SetTriggerSamplePosition(false, 0); 
 
   // Waveform originality is original    
   ECGWaveformGroup.SetWaveformOriginality(DicomWaveformOriginalityType.Original); 
 
   // Just in case!  
   Debug.Assert(ECGWaveformGroup.GetWaveformOriginality() == DicomWaveformOriginalityType.Original); 
 
   // Set the multiplex group label 
   ECGWaveformGroup.SetMultiplexGroupLabel("SCPECG Waveform"); 
   Debug.Assert(ECGWaveformGroup.GetMultiplexGroupLabel() == "SCPECG Waveform"); 
 
   // Set the Waveform padding value 
   // You can call DicomWaveformGroup.GetWaveformPaddingValue 
   // to get the waveform padding value 
   ECGWaveformGroup.SetWaveformPaddingValue(true, 32768); 
 
   InsertECGCChannel(ECGWaveformGroup, samples, count); 
 
   // Delete any waveform groups that already exist in the dataset 
   for (int index = 0; index < inputDS.WaveformGroupCount; index++) 
   { 
      inputDS.DeleteWaveformGroup(index); 
   } 
 
   // Insert the new waveform group into the dataset 
   inputDS.AddWaveformGroup(ECGWaveformGroup, 0); 
} 
 
// Add an ECG channel to the group 
void InsertECGCChannel(DicomWaveformGroup ECGWaveformGroup, short[] samples, int count) 
{ 
 
   // Add a channel to the group 
   DicomWaveformChannel ECGChannel = ECGWaveformGroup.AddChannel(1); 
   if (ECGChannel == null) 
   { 
      return; 
   } 
 
   // If we want to update a channel, we can first call  
   // DicomWaveformGroup.DeleteChannel and then call  
   // DicomWaveformGroup.AddChannel with the same  
   // index we passed to DeleteChannel 
 
 
   // Make sure that the channel really got added  
   // This is for the purposes of this sample only, because  
   // the check we did in the previous statement is enough 
   if ((ECGWaveformGroup.ChannelCount != 1) || 
         (ECGWaveformGroup.GetChannel(0) == null)) 
   { 
      return; 
   } 
 
   // We can call DicomWaveformChannel.GetWaveformGroup to access the waveform 
   // group that the channel belongs to 
 
   if (ECGChannel.Index != 0) 
   { 
      return; 
   } 
 
   /* 
      Set the channel samples 
      The data we are setting in here is 16 bit data. 
      We would call SetChannelSamples8 if the data were 8 bit. 
      We can also call SetChannelSamples32, which will set the data 
      as either 8-bit or 16-bit depending on the sample interpretation 
   */ 
 
   if (ECGChannel.SetChannelSamples16(samples, count) != count) 
   { 
      return; 
   } 
 
   if ((ECGChannel.GetChannelSamples() == null) || (ECGChannel.GetChannelSamplesCount() == 0)) 
      return; 
 
   // Set the channel source and sensitivity 
   SetChannelSourceAndSensitivity(ECGChannel); 
 
   // Set the channel status 
   ECGChannel.SetChannelStatus(DicomChannelStatusType.OK); 
   if (ECGChannel.GetChannelStatus() != DicomChannelStatusType.OK) 
   { 
      return; 
   } 
 
   // Set the channel time skew. You can call  
   // LDicomWaveformChannel::GetChannelTimeSkew to get the time skew 
   // You can also call DicomWaveformChannel.SetChannelSampleSkew 
   // And DicomWaveformChannel.GetChannelSampleSkew to set and get  
   // the channel samples skew 
   ECGChannel.SetChannelTimeSkew(0.000000); 
 
   // Set the waveform channel number 
   ECGChannel.SetWaveformChannelNumber(true, 0); 
   if (ECGChannel.GetWaveformChannelNumber() != 0) 
      return; 
 
   // Set the channel label 
   ECGChannel.SetChannelLabel("First Channel"); 
 
   if (ECGChannel.GetChannelLabel() != "First Channel") 
      return; 
 
   // No channel offset 
   // You can also call DicomWaveformChannel.GetChannelOffset 
   // To get the channel offset 
 
   ECGChannel.SetChannelOffset(false, 0.0); 
 
   // Set filter low frequency 
   // You can also call DicomWaveformChannel.GetFilterLowFrequency 
   // To get the filter low frequency 
 
   ECGChannel.SetFilterLowFrequency(true, 0.050); 
 
   // Set filter high frequency 
   // You can also call DicomWaveformChannel.GetFilterHighFrequency 
   // To get the filter high frequency 
 
   ECGChannel.SetFilterHighFrequency(true, 100.00); 
 
   // Set the channel minimum value 
   ECGChannel.SetChannelMinimumValue(true, -386); 
 
   // Set the channel maximum value 
   ECGChannel.SetChannelMaximumValue(true, 1264); 
 
 
   if (ECGChannel.GetChannelMinimumValue() != -386) 
      return; 
 
   if (ECGChannel.GetChannelMaximumValue() != 1264) 
      return; 
 
   /* 
      You can also call the following functions to set and get the notch  
      filter frequency and bandwidth 
      DicomWaveformChannel.SetNotchFilterFrequency 
      DicomWaveformChannel.GetNotchFilterFrequency 
      DicomWaveformChannel.SetNotchFilterBandwidth 
      DicomWaveformChannel.GetNotchFilterBandwidth 
   */ 
 
   // Last, but not least, set the channel annotations!  
   SetChannelAnnotations(ECGChannel); 
} 
 
//Set the channel source and sensitivity 
void SetChannelSourceAndSensitivity(DicomWaveformChannel channel) 
{ 
 
   // Let's use the DICOM context group tables!  
 
   ///////////////////////Channel Source///////////////////////// 
   // Load the ECG Leads table  
 
   DicomContextGroupTable.Instance.Load(DicomContextIdentifierType.CID3001); 
   DicomContextGroup ECGLeadsGroup = DicomContextGroupTable.Instance.Find(DicomContextIdentifierType.CID3001); 
   if (ECGLeadsGroup != null) 
   { 
      DicomContextIdentifierType type = ECGLeadsGroup.ContextIdentifier; 
 
      DicomCodedConcept codedConcept = DicomContextGroupTable.Instance.FindCodedConcept(ECGLeadsGroup, "SCPECG", "5.6.3-9-1"); 
      if (codedConcept != null) 
      { 
         DicomCodeSequenceItem codeSequenceItem = new DicomCodeSequenceItem(); 
         codeSequenceItem.CodeValue = codedConcept.CodeValue; 
         codeSequenceItem.CodingSchemeDesignator = codedConcept.CodingSchemeDesignator; 
         codeSequenceItem.CodingSchemeVersion = codedConcept.CodingSchemeVersion; 
         codeSequenceItem.CodeMeaning = codedConcept.CodeMeaning; 
 
         // Set the channel source 
         channel.SetChannelSource(codeSequenceItem); 
         // You can call DicomWaveformChannel.GetChannelSource to get the channel source 
      } 
   } 
 
   ///////////////////////Channel Sensitivity//////////////////////// 
   DicomContextGroupTable.Instance.Load(DicomContextIdentifierType.CID3082); 
   // Cardiology Units of Measurement 
   DicomContextGroup cardiologyUnitsGroup = DicomContextGroupTable.Instance.Find(DicomContextIdentifierType.CID3082); 
   if (cardiologyUnitsGroup != null) 
   { 
      DicomCodedConcept codedConcept = DicomContextGroupTable.Instance.FindCodedConcept(cardiologyUnitsGroup, "UCUM", "mV"); 
      if (codedConcept != null) 
      { 
         DicomCodeSequenceItem sourceSequenceItem = new DicomCodeSequenceItem(); 
 
         sourceSequenceItem.CodeValue = codedConcept.CodeValue; 
         sourceSequenceItem.CodingSchemeDesignator = codedConcept.CodingSchemeDesignator; 
         sourceSequenceItem.CodingSchemeVersion = codedConcept.CodingSchemeVersion; 
         sourceSequenceItem.CodeMeaning = codedConcept.CodeMeaning; 
 
         // Set the channel sensitivity 
         channel.SetChannelSensitivity(true, 0.001220, sourceSequenceItem, 1.0, 0.0); 
 
         // You can call DicomWaveformChannel.GetChannelSensitivity to get the channel sensitivity 
      } 
   } 
} 
 
// Add annotations for the channel 
void SetChannelAnnotations(DicomWaveformChannel channel) 
{ 
 
   // Delete any existing channel annotations 
   for (int index = 0; index < channel.GetAnnotationCount(); index++) 
   { 
      if (channel.GetAnnotation(index) != null) 
      { 
         channel.DeleteAnnotation(index); 
      } 
   } 
 
   DicomWaveformAnnotation waveformAnnotation = new DicomWaveformAnnotation(); 
   DicomCodeSequenceItem codedName = new DicomCodeSequenceItem(); 
 
   codedName.CodeValue = "8867-4"; 
   codedName.CodeMeaning = "Heart rate"; 
   codedName.CodingSchemeDesignator = "LN"; 
   codedName.CodingSchemeVersion = "19971101"; 
 
   waveformAnnotation.CodedName = codedName; 
   //Over here we can access other properties such as  
   // waveformAnnotation.CodedValue and waveformAnnotation.UnformattedTextValue  
 
   DicomCodeSequenceItem measurementUnits = new DicomCodeSequenceItem(); 
 
   measurementUnits.CodeValue = "{H.B.}/min"; 
   measurementUnits.CodeMeaning = "Heart beat per minute"; 
   measurementUnits.CodingSchemeDesignator = "UCUM"; 
   measurementUnits.CodingSchemeVersion = "1.4"; 
 
   waveformAnnotation.MeasurementUnits = measurementUnits; 
 
   waveformAnnotation.SetNumericValue(new double[] { 69.00 }, 1); 
 
   channel.AddAnnotation(waveformAnnotation); 
} 
Imports Leadtools 
Imports Leadtools.Dicom 
 
Public Sub InsertECGCWaveform(ByVal inputDS As DicomDataSet, ByVal samples As Short(), ByVal count As Integer) 
 
   ' Our new waveform group 
   Dim ECGWaveformGroup As DicomWaveformGroup = New DicomWaveformGroup() 
 
   ' Reset the waveform group, we don't  
   ' really need to call this!  
   ECGWaveformGroup.Reset() 
 
   ' Set the number of samples per channel. You can call  
   ' DicomWaveformGroup.GetNumberOfSamplesPerChannel to get  
   ' the number of samples 
   ECGWaveformGroup.SetNumberOfSamplesPerChannel(count) 
 
   ' Set the sampling frequency. You can call  
   ' DicomWaveformGroup.GetSamplingFrequency to  
   ' get the sampling frequency 
   ECGWaveformGroup.SetSamplingFrequency(240.0) 
 
   ' Set sample interpretation 
   ECGWaveformGroup.SetSampleInterpretation(DicomWaveformSampleInterpretationType.Signed16BitLinear) 
 
   ' Just in case!  
   Debug.Assert(ECGWaveformGroup.GetSampleInterpretation() = DicomWaveformSampleInterpretationType.Signed16BitLinear) 
 
   ' No Multiplex Group Time Offset 
   ' You can call DicomWaveformGroup.GetMultiplexGroupTimeOffset  
   ' to get the time offset 
   ECGWaveformGroup.SetMultiplexGroupTimeOffset(False, 0.0) 
 
   ' No Trigger Time Offset 
   ' You can call DicomWaveformGroup.GetTriggerTimeOffset  
   ' to get the trigger time offset 
   ECGWaveformGroup.SetTriggerTimeOffset(False, 0.0) 
 
   ' No Trigger Sample Position 
   ' You can call DicomWaveformGroup.GetTriggerSamplePosition 
   ' to get the trigger sample position 
   ECGWaveformGroup.SetTriggerSamplePosition(False, 0) 
 
   ' Waveform originality is original    
   ECGWaveformGroup.SetWaveformOriginality(DicomWaveformOriginalityType.Original) 
 
   ' Just in case!  
   Debug.Assert(ECGWaveformGroup.GetWaveformOriginality() = DicomWaveformOriginalityType.Original) 
 
   ' Set the multiplex group label 
   ECGWaveformGroup.SetMultiplexGroupLabel("SCPECG Waveform") 
   Debug.Assert(ECGWaveformGroup.GetMultiplexGroupLabel() = "SCPECG Waveform") 
 
   ' Set the Waveform padding value 
   ' You can call DicomWaveformGroup.GetWaveformPaddingValue 
   ' to get the waveform padding value 
   ECGWaveformGroup.SetWaveformPaddingValue(True, 32768) 
 
   InsertECGCChannel(ECGWaveformGroup, samples, count) 
 
   ' Delete any waveform groups that already exist in the dataset 
   Dim index As Integer = 0 
   Do While index < inputDS.WaveformGroupCount 
      inputDS.DeleteWaveformGroup(index) 
      index += 1 
   Loop 
 
   ' Insert the new waveform group into the dataset 
   inputDS.AddWaveformGroup(ECGWaveformGroup, 0) 
End Sub 
 
' Add an ECG channel to the group 
Private Sub InsertECGCChannel(ByVal ECGWaveformGroup As DicomWaveformGroup, ByVal samples As Short(), ByVal count As Integer) 
 
   ' Add a channel to the group 
   Dim ECGChannel As DicomWaveformChannel = ECGWaveformGroup.AddChannel(1) 
   If ECGChannel Is Nothing Then 
      Return 
   End If 
 
   ' If we want to update a channel, we can first call  
   ' DicomWaveformGroup.DeleteChannel and then call  
   ' DicomWaveformGroup.AddChannel with the same  
   ' index we passed to DeleteChannel 
 
 
   ' Make sure that the channel really got added  
   ' This is for the purposes of this sample only, because  
   ' the check we did in the previous statement is enough 
   If (ECGWaveformGroup.ChannelCount <> 1) OrElse (ECGWaveformGroup.GetChannel(0) Is Nothing) Then 
      Return 
   End If 
 
   ' We can call DicomWaveformChannel.GetWaveformGroup to access the waveform 
   ' group that the channel belongs to 
 
   If ECGChannel.Index <> 0 Then 
      Return 
   End If 
 
   ' 
   'Set the channel samples 
   'The data we are setting in here is 16 bit data. 
   'We would call SetChannelSamples8 if the data were 8 bit. 
   'We can also call SetChannelSamples32, which will set the data 
   'as either 8-bit or 16-bit depending on the sample interpretation 
   ' 
 
   If ECGChannel.SetChannelSamples16(samples, count) <> count Then 
      Return 
   End If 
 
   If (ECGChannel.GetChannelSamples() Is Nothing) OrElse (ECGChannel.GetChannelSamplesCount() = 0) Then 
      Return 
   End If 
 
   ' Set the channel source and sensitivity 
   SetChannelSourceAndSensitivity(ECGChannel) 
 
   ' Set the channel status 
   ECGChannel.SetChannelStatus(DicomChannelStatusType.OK) 
   If ECGChannel.GetChannelStatus() <> DicomChannelStatusType.OK Then 
      Return 
   End If 
 
   ' Set the channel time skew. You can call  
   ' LDicomWaveformChannel::GetChannelTimeSkew to get the time skew 
   ' You can also call DicomWaveformChannel.SetChannelSampleSkew 
   ' And DicomWaveformChannel.GetChannelSampleSkew to set and get  
   ' the channel samples skew 
   ECGChannel.SetChannelTimeSkew(0.0) 
 
   ' Set the waveform channel number 
   ECGChannel.SetWaveformChannelNumber(True, 0) 
   If ECGChannel.GetWaveformChannelNumber() <> 0 Then 
      Return 
   End If 
 
   ' Set the channel label 
   ECGChannel.SetChannelLabel("First Channel") 
 
   If ECGChannel.GetChannelLabel() <> "First Channel" Then 
      Return 
   End If 
 
   ' No channel offset 
   ' You can also call DicomWaveformChannel.GetChannelOffset 
   ' To get the channel offset 
 
   ECGChannel.SetChannelOffset(False, 0.0) 
 
   ' Set filter low frequency 
   ' You can also call DicomWaveformChannel.GetFilterLowFrequency 
   ' To get the filter low frequency 
 
   ECGChannel.SetFilterLowFrequency(True, 0.05) 
 
   ' Set filter high frequency 
   ' You can also call DicomWaveformChannel.GetFilterHighFrequency 
   ' To get the filter high frequency 
 
   ECGChannel.SetFilterHighFrequency(True, 100.0) 
 
   ' Set the channel minimum value 
   ECGChannel.SetChannelMinimumValue(True, -386) 
 
   ' Set the channel maximum value 
   ECGChannel.SetChannelMaximumValue(True, 1264) 
 
 
   If ECGChannel.GetChannelMinimumValue() <> -386 Then 
      Return 
   End If 
 
   If ECGChannel.GetChannelMaximumValue() <> 1264 Then 
      Return 
   End If 
 
   ' 
   'You can also call the following functions to set and get the notch 
   'filter frequency and bandwidth 
   'DicomWaveformChannel.SetNotchFilterFrequency 
   'DicomWaveformChannel.GetNotchFilterFrequency 
   'DicomWaveformChannel.SetNotchFilterBandwidth 
   'DicomWaveformChannel.GetNotchFilterBandwidth 
   ' 
 
   ' Last, but not least, set the channel annotations!  
   SetChannelAnnotations(ECGChannel) 
End Sub 
 
'Set the channel source and sensitivity 
Private Sub SetChannelSourceAndSensitivity(ByVal channel As DicomWaveformChannel) 
 
   ' Let's use the DICOM context group tables!  
 
   '/////////////////////Channel Source///////////////////////// 
   ' Load the ECG Leads table  
 
   DicomContextGroupTable.Instance.Load(DicomContextIdentifierType.CID3001) 
   Dim ECGLeadsGroup As DicomContextGroup = DicomContextGroupTable.Instance.Find(DicomContextIdentifierType.CID3001) 
   If Not ECGLeadsGroup Is Nothing Then 
      Dim type As DicomContextIdentifierType = ECGLeadsGroup.ContextIdentifier 
 
      Dim codedConcept As DicomCodedConcept = DicomContextGroupTable.Instance.FindCodedConcept(ECGLeadsGroup, "SCPECG", "5.6.3-9-1") 
      If Not codedConcept Is Nothing Then 
         Dim codeSequenceItem As DicomCodeSequenceItem = New DicomCodeSequenceItem() 
         codeSequenceItem.CodeValue = codedConcept.CodeValue 
         codeSequenceItem.CodingSchemeDesignator = codedConcept.CodingSchemeDesignator 
         codeSequenceItem.CodingSchemeVersion = codedConcept.CodingSchemeVersion 
         codeSequenceItem.CodeMeaning = codedConcept.CodeMeaning 
 
         ' Set the channel source 
         channel.SetChannelSource(codeSequenceItem) 
         ' You can call DicomWaveformChannel.GetChannelSource to get the channel source 
      End If 
   End If 
 
   '/////////////////////Channel Sensitivity//////////////////////// 
   DicomContextGroupTable.Instance.Load(DicomContextIdentifierType.CID3082) 
   ' Cardiology Units of Measurement 
   Dim cardiologyUnitsGroup As DicomContextGroup = DicomContextGroupTable.Instance.Find(DicomContextIdentifierType.CID3082) 
   If Not cardiologyUnitsGroup Is Nothing Then 
      Dim codedConcept As DicomCodedConcept = DicomContextGroupTable.Instance.FindCodedConcept(cardiologyUnitsGroup, "UCUM", "mV") 
      If Not codedConcept Is Nothing Then 
         Dim sourceSequenceItem As DicomCodeSequenceItem = New DicomCodeSequenceItem() 
 
         sourceSequenceItem.CodeValue = codedConcept.CodeValue 
         sourceSequenceItem.CodingSchemeDesignator = codedConcept.CodingSchemeDesignator 
         sourceSequenceItem.CodingSchemeVersion = codedConcept.CodingSchemeVersion 
         sourceSequenceItem.CodeMeaning = codedConcept.CodeMeaning 
 
         ' Set the channel sensitivity 
         channel.SetChannelSensitivity(True, 0.00122, sourceSequenceItem, 1.0, 0.0) 
 
         ' You can call DicomWaveformChannel.GetChannelSensitivity to get the channel sensitivity 
      End If 
   End If 
End Sub 
 
' Add annotations for the channel 
Private Sub SetChannelAnnotations(ByVal channel As DicomWaveformChannel) 
 
   ' Delete any existing channel annotations 
   Dim index As Integer = 0 
   Do While index < channel.GetAnnotationCount() 
      If Not channel.GetAnnotation(index) Is Nothing Then 
         channel.DeleteAnnotation(index) 
      End If 
      index += 1 
   Loop 
 
   Dim waveformAnnotation As DicomWaveformAnnotation = New DicomWaveformAnnotation() 
   Dim codedName As DicomCodeSequenceItem = New DicomCodeSequenceItem() 
 
   codedName.CodeValue = "8867-4" 
   codedName.CodeMeaning = "Heart rate" 
   codedName.CodingSchemeDesignator = "LN" 
   codedName.CodingSchemeVersion = "19971101" 
 
   waveformAnnotation.CodedName = codedName 
 
   'Over here we can access other properties such as  
   'waveformAnnotation.CodedValue and waveformAnnotation.UnformattedTextValue  
 
   Dim measurementUnits As DicomCodeSequenceItem = New DicomCodeSequenceItem() 
 
   measurementUnits.CodeValue = "{H.B.}/min" 
   measurementUnits.CodeMeaning = "Heart beat per minute" 
   measurementUnits.CodingSchemeDesignator = "UCUM" 
   measurementUnits.CodingSchemeVersion = "1.4" 
 
   waveformAnnotation.MeasurementUnits = measurementUnits 
 
   waveformAnnotation.SetNumericValue(New Double() {69.0}, 1) 
 
   channel.AddAnnotation(waveformAnnotation) 
End Sub 

Requirements

Target Platforms

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