I am developing a package in R (3.4.3) that has some internal data and I would like to be able to let users refresh it without having to do too much work. But let me be more specific.
The package contains several functions that rely on multiple parameters but I am really only exporting wrapper functions that do all the work. Because there is a large number of parameters to pass to those wrapper functions, I am putting them in a .csv file and passing them as a list. The data is therefore a simple .csv file called param.csv with the names of the parameters in one column and their value in the next column
parameter_name,parameter_value
ticker, SPX Index
field, PX_LAST
rolling_window,252
upper_threshold,1
lower_threshold,-1
signal_positive,1
signal_neutral,0
signal_negative,-1
I process it running
param.df <- read.csv(file = "param.csv", header = TRUE, sep = ",")
param.list <- split(param.df[, 2], param.df[, 1])
and I put the list inside the package like this
usethis::use_data(param.list, overwrite = TRUE)
Then, when reset the R interactive window and execute
devtools::document()
devtools::load_all()
devtools::install()
require(pkg)
everything works out great, the data is available and can be passed to functions.
First problem: when I change
param.csv, save it and repeat the above four lines of code, the internalparam.listis not updated. Is there something I am missing here ? Or is it by nature that the developer of the package should runusethis::use_data(param.list, overwrite = TRUE)each time he changes the.csvfile where the data comes from?
Because it is intended to be a sort of map, the users will want to tweak parameters for (manual) model calibration. To try and solve this issue I let users provide the functions with their own parameter list (as a .csv file like before). I have a function get_param_list("path/to/file.csv") that does exactly the same processing that is done above and returns the list. It allows the users to pass their own parameter list. De facto, the internal data param.list is considered a default setting of parameters.
Second Problem: I'd like to let users modify this default list of parameters
param.listfrom outside the package in a safe way.
So since the internal object is a list, the users can simply modify the element of their choice in the list from outside the package. But that is pretty dangerous in my mind because users could - forget parameters, so I have default values inside the functions for that case - replace a parameter with another type which can provoke an error or worse, side effects.
Is there a way to let users modify the internal list of parameters without opening the package ? For example I had thought about a function that could replace the .csv file by a new one provided by the user but this brings me back to the First Problem, when I restart the R prompt and reinstall the package, nothing happens unless I usethis::use_data(param.list, overwrite = TRUE) from inside the package. Would another type of data be more useful (e.g. make the data internal) ?
This is my first question on this website but I realize it's quite long and might be taken as a coding style question. But if anyone can see an obvious mistake or misunderstanding of package development in R from my side that would really help me.
Cheers
