elegant | tools and pipelines for zplab C. elegans data

So I'm try to use ScrollViewReader to programmatically scroll a horizontal scroll view. I thought it would work like scrollToItem with .centeredHorizontally in UIKit, and for the most part it does, but the last few elements in the scroll view are being forcefully scrolled to the center of the screen, despite the fact that the scroll view isn't normally able to scroll that far over (without snapping back after releasing the drag, at least). This ends up creating white space across the trailing half of the screen.

I've seen some other questions about this and it seems like the general opinion is that it's not a bug? On the one hand I suppose we're telling the scroll view to center the item, and it's doing just that -- so, not a bug? On the other hand, that's not how similar functionality worked in UIKit. Also, this behavior is only happening on the trailing end of the scroll view! If it was the intended behavior I would expect that scrolling to the first element in the scroll view using .center anchor would force it into the center of the screen and leave leading white space, but this doesn't happen.

Is there an elegant solution to this? Or do we have to calculate the width of our elements + spacing and figure out based on the screen width whether we should anchor .center or just scroll to the last element with anchor .trailing in order to replicate the UIKit behavior?

I have some pretty complicated objects. They contain member variables of other objects. I understand the beauty of copy constructors cascading such that the default copy constructor can often work. But, the situation that may most often break the default copy constructor (the object contains some member variables which are pointers to its other member variables) still applies to a lot of what I've built. Here's an example of one of my objects, its constructor, and the copy constructor I've written:

I am translating a code from Python to Julia. I have the following array:

I am trying to define a function that takes a data frame or table as input with a specific number of ID columns (e.g., 2 or 3 ID columns), and the remaining columns are NAME1, NAME2, ..., NAMEK (numeric columns). The output should be a data table that consists of the same ID columns as before plus one additional ID column that groups each unique pairwise combination of the column names (NAME1, NAME2, ...). In addition, we must gather the actual values of the numeric columns into two new columns based on the ID column; an example with two ID columns and three numeric columns:

I have a matrix with many rows and columns, of the nature

I have a list with strings as below.

I have a nested list of lists which contains some data frames. However, the data frames can appear at any level in the list. What I want to end up with is a flat list, i.e. just one level, where each element is only the data frames, with all other things discarded.

I have come up with a solution for this, but it looks very clunky and I am sure there ought to be a more elegant solution.

Importantly, I'm looking for something in base R, that can extract data frames at any level inside the nested list. I have tried unlist() and dabbled with rapply() but somehow not found a satisfying solution.

Example code follows: an example list, what I am actually trying to achieve, and my own solution which I am not very happy with. Thanks for any help!

I have a huge dataset and wish to replace values in certain columns (VAR1, VAR2) with NA if they do not start with AA or DD.

Data:

Assume I have the following data frame: