Channels and Channel References
- Updated2024-09-12
- 6 minute(s) read
Channels and Channel References
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»DIAdem Settings»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. If you do not specify a group index, DIAdem uses the default group. |
| 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 name | Use 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. |
| /Channel names []/Channel names /[Channel index] []/[Channel index] | Use the setting without specifying a group name or group index in order to access channels from the default group. In DIAdem VIEW you cannot access the default group with this syntax. The following example saves the result of the calculation in the default group:
|
 | Note If you access channels with channel index and group index, note that channel indexes and group indexes may have different numbers during the runtime of an event than at the end of the event. 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. When naming channels, do not use numbers only and avoid single or double quotation marks. Although such a name is not prohibited, it may cause issues in several places. For more information about naming data sets, channel groups, channels, and custom properties, refer to the Name Conventions page. |
The following table illustrates the relation between the structure view in the Data Portal and the group index combined with the channel name and the group name combined with the channel name.
| Data Structure | [Group Index]/Channel Name | Group Name/Channel Name |
|---|---|---|
|
Dataset |
|
|
Group_A
Channel_C 