Preference for label of reference lines on plot?

[Schiano-NOAA]

I am working on a feature to add reference lines for each model input into a plotting function. For example:

plot_spawning_biomass(
  dat = list("sable23"=sable23, "sable25"=sable25),
  module = "DERIVED_QUANTITIES",
  ref_line = c("msy"=50000,"msy"=150000)
)

Questions around this plot:

1. Do you have a preference for the label name for the reference line. (e.g. "model name ref name, label of plot with ref name and potentially the same color as the difference in the lines on the graph, ect)
2. Does anyone have any suggestions with placement and size of the reference line label? It can be large depending on how large or small the plot is saved/viewed as. The names sometimes overlap when reference line values are close to one another.

TIA

[Schiano-NOAA]

@nmfs-ost/asar-collaborators

[chantelwetzel-noaa]

@Schiano-NOAA Thank you for asking for feedback. In the example plot, I am not sure what the dashed horizontal lines represent, but my preference would be to include the labels for those lines in the figure legend. If I were creating this plot, I would do the following:

1. Only include the line legend, with the unique colors, and not include the fill items in the legend since that is redundant.
2. If this figure is showing estimates from two separate models, I would include only that text in the legend next to the lines. In this example, I would label them as 2025 and 2023 only. I think the best approach here would be to allow users to customize the labels depending on what is being plotted which I think could be done easily by having users specify the names in the data frame being passed to the plotting function (e.g., dat arguement in example code).
3. If there needed to be horizontal dashed lines added as well, I would use the same colors that are used to plot the time series for each model (e.g., black and seafoam) for those dashed horizontal lines to indicate which line corresponds to which model.
4. I would add an item to the legend for each of the horizontal lines labeling what reference point they are showing (e.g., B40 - 2023). An alternative would be to add the text just above the line similar to this example, but there is no "best" placement since it will depend on the time series being plotted. However, since this is a ggplot, users could adjust the text placement if needed, but that might be tedious.

[Schiano-NOAA]

@chantelwetzel-noaa Thanks so much for this feedback! It is super helpful to hear.

For #1, this is an issue I am trying to work out because we definitely don't want both (so agreed 😄 ).

For #2, the name for the model you are comparing is inherited through the name in the input dat list list("sable23"=sable23, "sable25"=sable25) so you could easily just change this to 2023 and 2025. Do you think that solution is what you are looking for?

3&4 are excellent suggestions. I think I can get that worked into the plot.

[chantelwetzel-noaa]

I think #2 is covered; I was just be exhaustive in my comments, when I probably didn't need to be. 🫠

[Schiano-NOAA]

It's appreciated nonetheless!

[lisaailloud-NOAA]

These are all great suggestions. I think the label could stay on the plot if the size was adjusted down to be slightly smaller than the axis titles and if it just said SBmsy or SSBmsy (the color would indicate which model it refers to so I don't think it is necessary in the label). In that case though it would be better to have it adjusted to the left of the plot so the terminal years are easier to see.