In KNIME 5.1, the new Cell Extractor node looks to be a useful addition, in that it allows us to quickly pull a specific value from a table at a given row and column.
Currently it creates both a 1x1 table, and a flow variable with the name “extracted_cell”
I would imagine the primary use case for this node will be the creation of a flow variable to be used downstream. Certainly that is how I would expect to use it.
Given that we cannot rename flow variables, I feel this node would be improved if it allowed us to specify the name of the variable (and column name) that it is going to create.
As an example of why this is important…
Say I am extracting three cells and I want to use those extracted values as variables later in my flow.
I ought to be able to do it with something like this:
But currently, I have to write something like this:
or this :
(fewer nodes, but potential “column name clash” makes for messy renaming!)
which feels like a lot of nodes to make three variables!
This would improve efficiency and the general usability of this great new node.
This actually made me think that if there was a
variable renamer node, similar to the
column renamer node, it might be more generic…
Merge Variables should handle same variable name case, it should auto rename the same variable name to
Hi @HaveF, I agree that a “variable renamer” would be useful, but sadly I don’t think we will see one any time soon any more than we are going to see a (much requested) “variable filter” (and probably for similar technical reasons, although I can only guess at what they are).
My own view is that any node that creates variables or columns should have the option to specify the name that is to be generated. This would be a whole lot slicker and more obvious especially for new users.
Whenever I have to put in a Column Renamer simply because the previous node doesn’t allow me to specify the column name, this to me is added workflow clutter and noise, and ultimately inefficient use of desktop real estate and time.
edit: wrt Merge Variables - the merging of three variables with the same name results in a single variable of that name, with the “chosen” value being the copy from the uppermost input port that supplies that variable, unlike the equivalent column behaviour where #n is appended.
I agree Advice on new node is a reasonable way to make this happen