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Channels and Channel References

DIAdem 2010 Help

Edition Date: June 2010

Part Number: 370859H-01

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DIAdem stores data in channels. To access channel data, you need unique channel references in dialog boxes and scripts. For example, to compare channels from different channel groups, you must give the channels unique names. If you select channels in a dialog box or record commands in a dialog box, DIAdem automatically references the correct channel.
The default channel reference consists of the group index and the channel name. To modify the default setting, select Settings»Options»General. You also can reference channels with any combination of the group name or the group index with the channel name or the channel index. The channel index is the position of the channel in the group, and the group index is the position of the group in the data set.

[Group index]/Channel name Default setting. Use this setting if you do not know the names of the channel groups or if the names might change, whereas the names of the channels to be compared are the same in different channel groups. The order of the channels in a group can change.
[Group index]/[Channel index]Use this setting if you do not know the names of the channel groups and of the channels, or if the names can change, but the indexes of the channels to be compared are the same in different channel groups.
Group name/[Channel index]Use this setting if you do not know the names of the channels, or if the names can change, but the indexes of the channels to be compared are the same in different channel groups. The order of the groups can change.
Group name/Channel nameUse this setting if the channel groups have different names and the channels have different names, and you need both names for a unique channel reference. The channel index and the group index can be different. The order of the channels in a group and the order of the groups can change.
Only channel nameUse this setting if the Data Portal has only one channel group or if the channel references have to be compatible with earlier DIAdem versions. The channel reference does not include a group name. The channel reference is ambiguous if several channels in different channel groups of the Data Portal have the same name. DIAdem then uses the channel with this name and the lowest channel number, in dialog boxes or scripts.
Channel numberUse this setting if the channel references must be compatible with earlier DIAdem versions and you are sure that the order of channel numbers has not changed. The channel names are irrelevant.
The channel numbers can change, for example, if you delete channels.
Note  For more information about naming data sets, channel groups, channels, and custom properties, refer to the Name Conventions Help page.
Note  If you set a slash / before the channel name or the channel index, DIAdem uses the default channel group.
Note  DIAdem uses unique names for channel groups, so that the name of a channel group cannot occur twice. If you load a data set into the DIAdem Data Portal and the name of a channel group already exists, DIAdem appends a number to the new group name to distinguish between the channel group names. A channel name must also be unique within a channel group.

The following table illustrates the relation between the structure view in the Data Portal and the group index combined with the channel name, the group name combined with the channel name, and the assignment to possible channel numbers. The indexes and names are clearly structured in the Data Portal hierarchy. However, channel numbers can be assigned to any channels. Use the indexes and names of the groups and channels in layouts and scripts.

Data structure [Group index]/Channel name Group name/Channel name Possible
Channel numbers

Dataset

  Group_A

     Channel_A  

      Channel_B  

     Channel_C  

  Group_B

     Channel_A  

      Channel_B 

     Channel_C  

  Group_C

         Channel_A  

          Channel_B 

         Channel_C  

 

      "[1]/Channel_A"     

      "[1]/Channel_B"     

      "[1]/Channel_C"    

      "[2]/Channel_A"  

      "[2]/Channel_B"  

      "[2]/Channel_C"  

      "[3]/Channel_A"    

      "[3]/Channel_B"

      "[3]/Channel_C"   

 

  "Group_A/Channel_A"   

  "Group_A/Channel_B"   

  "Group_A/Channel_C"   

  "Group_B/Channel_A"   

  "Group_B/Channel_B"   

  "Group_B/Channel_C"   

  "Group_C/Channel_A"   

  "Group_C/Channel_B"   

  "Group_C/Channel_C"   

 

7

8

9

1

2

3

6

5

4

 


 

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