R CMD check: no visible binding for global variable ‘mypkgdata’ [duplicate] - r

This question already has answers here:
No visible binding for global variable Note in R CMD check
(5 answers)
Closed 4 years ago.
This question is slightly different from others on this subject -- I do indeed have a variable called "mypkgdata":
I am writing a package which ships with a data set. This data set is needed for calculations from within the package. In the DESCRIPTION file, I have specified "LazyData" for that purpose, such that the data set is always around when anyone loads the package. When I run the check, however, I get:
.getmodules2: no visible binding for global variable ‘mypkgdata’
What is the correct way of solving this problem?

If you have LazyData: TRUE in your DESCRIPTION file than the following should work:
x <- MyPackageName::mypkgdata
# ... your calculations using x
I get your note also, if I trie calling it without the MyPackageName:: part.

Here is how I have solved it. I create a custom environment in the package, load the data set in this environment, and wrote a function that returns the data set:
pkgEnv <- new.env(parent=emptyenv())
if(!exists("mypkgdata", pkgEnv)) {
data("mypkgdata", package="mypkg", envir=pkgEnv)
}
getMyPkgData <- function() {
pkgEnv[["mypkgdata"]]
}
And in the function that utilizes "mypkgdata", I write:
mypkgdata <- getMyPkgData()
Also, I gave up on lazy loading the data, as it is no longer necessary.

I think data from a package should not be flagged as invisible. However, a workaround is
if(getRversion() >= "2.15.1") utils::globalVariables("mypkgdata")
compare https://stackoverflow.com/a/17807914/3805440

Related

A note on graphics::curve() in R CMD check

I use the following code in my own package.
graphics::curve( foo (x) )
When I run R CMD check, it said the following note.How do I delete the NOTE?
> checking R code for possible problems ... NOTE
foo: no visible binding for global variable 'x'
Undefined global functions or variables:
x
Edit for the answers:
I try the answer as follows.
function(...){
utils::globalVariables("x")
graphics::curve( sin(x) )
}
But it did not work. So,..., now, I use the following code, instead
function(...){
x <-1 # This is not used but to avoid the NOTE, I use an object "x".
graphics::curve( sin(x) )
}
The last code can remove the NOTE.
Huuum, I guess, the answer is correct, but, I am not sure but it dose not work for me.
Two things:
Add
utils::globalVariables("x")
This can be added in a file of its own (e.g., globals.R), or (my technique) within the file that contains that code.
It is not an error to include the same named variables in multiple files, so the same-file technique will preclude you from accidentally removing it when you remove one (but not another) reference. From the help docs: "Repeated calls in the same package accumulate the names of the global variables".
This must go outside of any function declarations, on its own (top-level). While it is included in the package source (it needs to be, in order to have an effect on the CHECK process), but otherwise has no impact on the package.
Add
importFrom(utils,globalVariables)
to your package NAMESPACE file, since you are now using that function (unless you want another CHECK warning about objects not found in the global environment :-).

Changing defaults in a function inside a locked package [duplicate]

This question already has answers here:
Setting Function Defaults R on a Project Specific Basis
(2 answers)
Closed 9 years ago.
I am developing my first package and it is aimed at users who are new to R, so I am trying to minimize the amount of R skills required to use the package. As a result I want a function that changes defaults in other functions within my package. But I get the following error "cannot add bindings to a locked environment", which means the environment of the package is locked and I am not allowed to change the default values of its functions.
Here is an example that throws a similar error:
library(ggplot2)
assign(formals(geom_point)$position, "somethingelse", pos="package:ggplot2")
When I try assignInNamespace i get:
Error in bindingIsLocked(x, ns) : no binding for "identity"
assignInNamespace(formals(geom_point)$position,"somethingelse", pos = "package:ggplot2")
Here is an example of what I hope to achieve.
default <- function(x=c("A", "B", "C")){
x
}
default()
change.default <- function(x){
formals(default)$x <<- x # Notice the global assign
}
change.default(1:3)
default()
I am aware that this is far from the recommended approach, but I am willing to cut corners to improve the learning curve of the package. Is there a way to achieve this?
This question has been marked as a duplicate of Setting Function Defaults R on a Project Specific Basis. This is a different situation as this question concerns how to allow the user in a interactive session to change the defaults of a function - not how to actually do it. The old question could not have been solved with the options() function and it is therefore a different question.
I think the colloquial way to achieve what you want is via option and packages in fact do so, e.g., lattice (although they use special options) or ascii.
Furthermore, this is also done so in base R, e.g., the famous and notorious default for stringsAsFactors.
If you look at ?read.table or ?data.frame you get: stringsAsFactors = default.stringsAsFactors(). Inspecting this reveals:
> default.stringsAsFactors
function ()
{
val <- getOption("stringsAsFactors")
if (is.null(val))
val <- TRUE
if (!is.logical(val) || is.na(val) || length(val) != 1L)
stop("options(\"stringsAsFactors\") not set to TRUE or FALSE")
val
}
<bytecode: 0x000000000b068478>
<environment: namespace:base>
The relevant part here is getOption("stringsAsFactors") which produces:
> getOption("stringsAsFactors")
[1] TRUE
Changing it is achieved like this:
> options(stringsAsFactors = FALSE)
> getOption("stringsAsFactors")
[1] FALSE
To do what you want your package would need to set an option, and the function take it's values form the options. Another function could then change the options:
options(foo=c("A", "B", "C"))
default <- function(x=getOption("foo")){
x
}
default()
change.default <- function(x){
options(foo=x)
}
change.default(1:3)
default()
If you want your package to set the options when loaded, you need to create a .onAttach or .onLoad function in zzz.R. My afex package e.g., does this and changes the default contrasts. In your case it could look like the following:
.onAttach <- function(libname, pkgname) {
options(foo=c("A", "B", "C"))
}
ascii does it via .onLoad (I don't remember what is the exact difference, but Writing R Extensions will help).
Preferably, a function has the following things:
Input arguments
A function body which does something with those arguments
Output arguments
So in your situation where you want to change something about the behavior of a function, changing the input arguments in the best way to go. See for example my answer to another post.
You could also use an option to save some global settings (e.g. which font to use, which PATH the packages you use are stored), see the answer of #James in the question I linked above. But use these things sparingly as it makes the code hard to read. I would primarily use them read only, i.e. set them once (either by the package or the user) and not allow functions to change them.
The unreadability stems from the fact that the behavior of the function is not solely determined locally (i.e. by the code directly working with it), but also by settings far away. This makes it hard to determine what a function does by purely looking at the code calling it, but you have to dig through much more code to fully understand what is going on. In addition, what if other functions change those options, making it even harder to predict what a given function will do as it depends on the history of functions. And here comes my earlier recommendation for read-only options back into play, if these are read only, some of the problems about readability are lessened.

Save package settings between sessions

Is there a definitive way to save options or information pertaining to a certain package between sessions?
For example say somebody made a game and released it as an R package. If they wanted to save high scores and not have them reset each time R started a new session what would be the best way to do this? Currently I can only think of storing a file in the users home directory but I'm not sure if I like that approach.
This may be an approach. I created a dummy package with a dummy function (any function I create is bound to be a dummy function) and a data set I called scores that I set as follows:
scores <- NA
Then I created the package with the scores data set.
Then I used the following to change the data set from within R.
loc <- paste0(find.package("new"), "/Data")
unlink(paste0(loc, "/scores.rda"), recursive = TRUE, force = FALSE)
scores <- 10
save(scores, file=paste0(loc, "/scores.rda"))
Then when I unloaded the library and re loaded agin the data set now says:
> scores
[1] 10
Could this be modified to do what you want? You'd have to have it save in between somehow but am not sure on how to do this without messing with .Last function.
EDIT:
It appears this option is not viable in that when you compile as a package and use lazy load it saves the data sets as:
RData.rbd, RData.rbx, not as .rda files. That means the approach I use above is kinda worthless in that we want it to automatically be recognized.
EDIT2
This approach works and I tried it on a package I made. You can't do lazy load of the data and you have to either explicitly use data(scores) or use data(scores) inside of the function you're calling. I also assigned scores to .scores int he global.env the first time it was created and used exists inside the function to see if it exists. If `.scores. existed I assigned that to scores within the function. Once you unload the library and laod again you never have to worry about that again.
Maybe an alternative is to save this as a function somehow that can be altered using Josh's advice here: Permanently replacing a function
I guess there is no way to store settings without saving them to disk or a database, some way or another. It can be done silently though by putting the code below in your ~/.Rprofile. However, if you have packages that save settings in other ways than using options you need to add them manually.
I know this is exactly what you said you did not want, but it might spark some debate at least.
.Last <- function(){
my.options <- options()
save(my.options, file="~/.Roptions.Rdata")
}
.First <- function(){
tryCatch({
load("~/.Roptions.Rdata")
do.call(options, my.options)
rm(my.options)
}, error=function(...){})
}
To my suprise try(..., silent=TRUE) gives a warning on startup if ~/.Roptions.Rdata does not exist, which is why I used tryCatch instead.
The modern answer to this problem is well explained at https://blog.r-hub.io/2020/03/12/user-preferences/
I think I will be trying the hoardr package! Here is an example that worked for me :)
x <- hoardr::hoard()
x$cache_path_set("yourpackage", type = 'user_cache_dir')
x$mkdir()
scores<-data.frame(
user=c("one","two","three"),
score=c("500,200,1100")
)
save(scores,file = file.path(x$cache_path_get(), "scores.rdata"))
x$list()
x$details()
#new session
x <- hoardr::hoard()
x$cache_path_set("yourpackage", type = 'user_cache_dir')
x$list()
x$details()
load(file = file.path(x$cache_path_get(), "scores.rdata"))
PS - you can see a working example in the rnoaa package found on at github "opensci/rnoaa". Check their R/onload.r file! I can expand if needed.

Data inside a function (package creation)

If I need to use a data set inside a function (as a lookup table) inside of a package I'm creating do I need to explicitly load the data set inside of the function?
The function and the data set are both part of my package.
Is this the correct way to use that data set inside the function:
foo <- function(x){
x <- dataset_in_question
}
or is this better:
foo <- function(x){
x <- data(dataset_in_question)
}
or is there some approach I'm not thinking of that's correct?
There was a recent discussion about this topic (in the context of package development) on R-devel, numerous points of which are relevant to this question:
If only the options you provide are applicable to your example R himself (i.e., Brian Ripley) tells you to do:
foo <- function(x){
data("dataset_in_question")
}
This approach will however throw a NOTE in R CMD check which can be avoided in upcoming versions of R (or currently R devel) by using the globalVariables() function, added by John Chambers
The 'correct' approach (i.e., the one advocated by Brian Ripley and Peter Dalgaard) would be to use the LazyData option for your package. See this section of "Writing R Extensions".
Btw: I do not fully understand how your first approach should work. What should x <- dataset_in_question do? Is dataset_in_question a global Variable or defined previously?
For me it was necessary to use get() additionally to LazyData: true in DESCRIPTION file (see postig by #Henrik point 3) to get rid of the NOTE no visible binding for global variable .... My R version is 3.2.3.
foo <- function(x){
get("dataset_in_question")
}
So LazyData makes dataset_in_question directly accessible (without using data("dataset_in_question", envir = environment())) and get() is to satisfy R CMD check
HTH
One can just place the data set as a .rda file in the R folder as described by Hadley here: http://r-pkgs.had.co.nz/data.html#data-sysdata
Matthew Jockers uses this approach in the syuzhet package for data sets including the bing data set as seen at ~line 452 here: https://github.com/mjockers/syuzhet/blob/master/R/syuzhet.R
bing is not available to the user but is to the package as demonstrated by: syuzhet:::bing
Essentially, the command devtools::use_data(..., internal = TRUE) will set everything up in the way it's needed.

Cleaning up the workspace "hiding" objects [duplicate]

This question already has answers here:
hiding personal functions in R
(7 answers)
Closed 9 years ago.
It's getting to the point where I have about 100 or so personal functions that I use for line by line data analysis. I generally use f.<mnemonic> nomenclature for my functions, but I'm finding that they're starting to get in the way of my work. Is there any way to hide them from the workspace? Such that ls() doesn't show them, but I can still use them?
If you have that many functions which you use on a repeated basis, consider putting them into a package. They can then live in their own namespace, which removes ls() clutter and also allows you to remove the f. prefix.
You can also put the function definitions into a separate environment, and then attach() that environment. (This is similar to Hong Ooi's suggestion, without the added step of making that into a loadable package.) I have this code in my .Rprofile file to set up some utility functions I commonly use:
local(env = my.fns, { # create a new env. all variables created below go into this env.
foo <- function (bar) {
# whatever foo does
}
# put as many function definitions here as you want
})
attach(my.fns)
All the functions inside my.fns are now available at the commandline, but the only thing that shows up in ls() is my.fns itself.
Try this to leave out the "f-dots":
fless <- function() { ls(env=.GlobalEnv)[!grepl("^f\\.", ls(env=.GlobalEnv) )]}
The ls() function looks at objects in an environment. If you only used (as I initially did) :
fless <- function() ls()[!grepl("^f\\.", ls())]
You get ... nothing. Adding .GlobalEnv moves the focus for ls() out to the usual workspace. The indexing is pretty straightforward. You are just removing (with the ! operator) anything that starts with "f." and since the "." is a special character in regex expressions, you need to escape it, ... and since the "\" is also a special character, the escape needs to be doubled.
A couple of options not already mentioned are
objects with names beginning with . are not shown by ls() (by default; you can turn this on with argument all.names = TRUE in the ls() call), so you could rename everything to .f.<mnemonic> in the source files.
In a similar vein to #Aaron's answer but use sys.source() to to source directly into an environment.
An example using sys.source() is shown below:
env <- attach(NULL, name = "myenv")
sys.source(fnames, env)
where fnames is a list of file names/paths from which to read your functions.

Resources