Converting PyDataSet to DataSet

Ignition
1

Hello, i am trying to implement some filters on a table component, and the way I am trying to do it is by having the data(to be filtered) on a view property and then binding this to the table data and using a script transform to actually do the filtering. However my script cannot even be compiled, and i cant seem to be able to figure out why:

def transform(self, value, quality, timestamp):
	"""
	Transform the incoming value and return a result.

	Arguments:
		self: A reference to the component this binding is configured on.
		value: The incoming value from the binding or the previous transform.
		quality: The quality code of the incoming value.
		timestamp: The timestamp of the incoming value as a java.util.Date
	"""
	
	data=system.dataset.toPyDataSet(value)


	header=[]
	for i in range(data.getColumnCount()):
		header.append(data.getColumnName(i))


	newData=[]
	for row in data:
		if (self.checkFilters(row)): #Custom method to apply the filters
			newData.append(row)
	
	ret=system.dataset.toDataSet(header,newData)
	return ret

I am getting a scriptEval error at ret=system.dataset.toDataSet(header,newData)
(I cant seem to be able to copy-paste the error.)
newData is a PyList object (389x325)
header is also a PyList object(325)
Any help would be greatly appreciated!

2

Without a little more information on the error, Iā€™m not sure how much we can help.

If getColumnNames() returns a list of the column names, then why build your own list with a for loop? This seems like unneeded code.

3

Sorry about that, that was uncessary code, getColumnNames() returns an UnmodifiableRandomAccessList which causes an error in the conversion again, as the 1st Argument cannot be coerced into a PySequence.

I took a screenshot of the error message:

error
error637Ɨ671 55.6 KB

4

Try changing line 13 to this:

newData.append(list(row))
1 Like
5

The type cast to list as @code_skin suggests may do the trick. Barring that, I would shy away from the conversion to a PyDataSet. I just feel like it adds complexity without much reward in most cases. Here is how I would refactor your script:

def transform(self, value, quality, timestamp):
   """
   Transform the incoming value and return a result.

   Arguments:
   	self: A reference to the component this binding is configured on.
   	value: The incoming value from the binding or the previous transform.
   	quality: The quality code of the incoming value.
   	timestamp: The timestamp of the incoming value as a java.util.Date
   """
   
   headers = system.dataset.getColumnHeaders(value)

   newData=[]
   for rowIndex in range(value.rowCount):
       row = [value.getValueAt(rowIndex,col) for col in range(value.columnCount)]
       if self.checkFilters(row): #Custom method to apply the filters
           newData.append(row)

   return system.dataset.toDataSet(headers,newData)
6

The type casting to list, worked! Thank you very much all for your help and suggestions.

1 Like