Are there extra methods for dataset type tags?

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I have a memory tag of type Dataset. If I try to read the tag using a system.tag.readblocking() function the value property within the qualified value array is Dataset[56R, 7C] and the data within are seemingly inaccessible.

While browsing the forum I came across this post Reading from dataset query tag. In the opening code snippet, the poster used the method system.tag.read("datasetPath").value.getValueAt(rowIndex, 'columnName'). I tried this in the script console and I was able to access a cell, but I couldn't find this method anywhere in the User Manual documentation. Are there more functions like this? Where can I find them?

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.GetValueAt is a standard dataset method.
You can use any of the methods listed in the dataset doc:

and the system.dataset.* functions:

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One part missing from those docs is that jython will automatically expose attributes for java methods that follow the NetBeans naming conventions. And those attributes are more efficient than using the corresponding methods from jython.

So, use:
data.rowCount instead of data.getRowCount()
data.columnCount instead of data.getColumnCount()
data.columnNames instead of data.getColumnNames()
data.columnTypes instead of data.getColumnTypes()
data.qualityData instead of data.hasQualityData()

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Thanks. The disconnect I've been having is that I've been trying to create a dataset with the tag value using the toDataset function, thinking whatever was returned was not aready a dataset. Now that I've spelled it out, it seems a bit silly that I would think this would be the case.

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