Need to understand import/export to excel using Dynamo

We are trying to read an excel file to update the parameters into Revit. We are stuck at the linkage between the Revit and Excel.
There are two groups of code as follows:

  1. Read Excel cell range > Update Revit model elements of specified category “Mechanical Equipment”. Final output we are receiving as filtered list of elements and whole elements from categories.
  2. Read Revit model elements > Filter elements using list slicing to particular 2 nos. of mechanical equipment only based upon their mark values. Final output we are receiving as filtered list.

No we want Dynamo to update only the parameters of those 2 mechanical equipments (filtered through their mark values) rather than updating parameters of whole mechanical equipments.

When we are inputting the list of whole elements to be updated, it just updates the first 2 mechanical equipments and we want that it updates the tailored list of equipment that we sliced as list.

In other words, can we ask Dynamo to update parameters of only those 2 mechanical equipments [index : 130 & 131] rather than updating only first two [index : 0 & 1] mechanical equipments.

Can filtered “list” be converted back to “elements” to input in one of the Dynamo pre-defined modules. If this can be achieved, we will be grateful.

You could use a node to get the index of the desired mechanical equipment and then filter the total list of equipment to get the correct revit elements.

Can I ask why you wish the list filtered so early, isn’t it just the step where you write back the information that should be “filtered” it’s not optimal working with part-sets of data as you have no point of reference.

It is possible to grab the elements in python and return only some elements though this method is not optimal as it requires you to go and change the script every time your need changes.

There is a jumple of things off with the graph you uploaded: try this:

Thank you Jonathan. I actually need to go through documentation more thoroughly once. Wanted to confirm whether we have alternate processes/workflows for it or not. It happens frequently when we try to implement just the concept/logic of computer programming onto some new tool. We just started Dynamo a day ago. Generally, we need to manage data within ultra tight deadlines so we were trying our hands on it. We even tried it as per the image you shared, but as I said earlier, we need to go through documentation more thoroughly.

I have a little request for you to change the title of your topic to something more specific. As basically everyone on this forum is looking for help with Dynamo.
Edit: thanks!