What does the QuickTbl function do in this code? - r

I'm wondering how the author of the following page define the "QuickTbl" function. I assumed that it’s a user-defined function, rather than a function included in a library. I could not find any definition for the QuickTbl function.
https://alphahive.wordpress.com/2014/09/25/asset-pricing-9b-regime-switching/
If you look at the blog above, in MarkovEstPlot, QuickTbl is used as follows:
gg.m.tbl <- QuickTbl(mean.tbl,title='Estimates of Mean')
This should be defined somewhere in the blog (or in a library), but I could not find any.
(I am now asking the author for his/her help as well).

install.packages("basictabler")
library(“basictabler”)
and replacing QuickTbl by qtbl seems to work now.
For the basictabler library including qtbl function, please refer to: https://cran.r-project.org/web/packages/basictabler/vignettes/v01-introduction.html

Related

Is it unwise to modify the class of functions in other packages?

There's a bit of a preamble before I get to my question, so hang with me!
For an R package I'm working on I'd like to make it as easy as possible for users to partially apply functions inline. I had the idea of using the [] operators to call my partial application function, which I've name "partialApplication." What I aim to achieve is this:
dnorm[mean = 3](1:10)
# Which would be exactly equivalent to:
dnorm(1:10, mean = 3)
To achieve this I tried defining a new [] method for objects of class function, i.e.
`[.function` <- function(...) partialApplication(...)
However, R gives a warning that the [] method for function objects is "locked." (Is there any way to override this?)
My idea seemed to be thwarted, but I thought of one simple solution: I can invent a new S3 class "partialAppliable" and create a [] method for it, i.e.
`[.partialAppliable` = function(...) partialApplication(...)
Then, I can take any function I want and append 'partialAppliable' to its class, and now my method will work.
class(dnorm) = append(class(dnorm), 'partialAppliable')
dnorm[mean = 3](1:10)
# It works!
Now here's my question/problem: I'd like users to be able to use any function they want, so I thought, what if I loop through all the objects in the active environment (using ls) and append 'partialAppliable' to the class of all functions? For instance:
allobjs = unlist(lapply(search(), ls))
#This lists all objects defined in all active packages
for(i in allobjs) {
if(is.function(get(i))) {
curfunc = get(i)
class(curfunc) = append(class(curfunc), 'partialAppliable')
assign(i, curfunc)
}
}
Voilà! It works. (I know, I should probably assign the modified functions back into their original package environments, but you get the picture).
Now, I'm not a professional programmer, but I've picked up that doing this sort of thing (globally modifying all variables in all packages) is generally considered unwise/risky. However, I can't think of any specific problems that will arise. So here's my question: what problems might arise from doing this? Can anyone think of specific functions/packages that will be broken by doing this?
Thanks!
This is similar to what the Defaults package did. The package is archived because the author decided that modifying other package's code is a "very bad thing". I think most people would agree. Just because you can do it, does not mean it's a good idea.
And, no, you most certainly should not assign the modified functions back to their original package environments. CRAN does not like when packages modify the users search path unnecessarily, so I would be surprised if they allowed a package to modify other package's function arguments.
You could work around that by putting all the modified functions in an environment on the search path. But then you have to ensure that environment is always searched first, which means modifying the search path every time another package is loaded.
Changing arguments for functions in other packages also has the potential to make it very difficult for others to reproduce your results because they must have all your argument settings. Unless you always call functions with all their arguments specified, which defeats the purpose of what you're trying to do.

Atom editor: list and jump to definition(s) in project

As already mentioned I'm using the Atom text editor.
I'm currently working on a project written in c++. Of course it is desirable to jump to the definition of a function (in another project file), or other uses of this function (within the project). As far as I know this can be achieved with the packages I'll mention below. I want the package to display me the definition along with the path to the corresponding file which holds the definition and ideally the line where it occurs.
I'll welcome any comments and suggestions on how to solve the below mentioned problem(s) I have with (one of) the packages. Moreover I'm also thankful about pointers to possible solutions or posts concerning my problem(s), or how I can achieve this with another package.
Here is what I found / tried / did so far.
goto
Currently I'm using this package, although it is rather slow and does not show the arguments of the function as e.g. atom-ctags does, but it's the only package which displays me the files I need to see.
It shows me where the function is defined as well as where it is also used. However it does not show me the path to the file corresponding file it refers to.
atom-ctags
I also tried this package, building the tags is quite fast and moreover it show me the path to the file. But this package only lists the .cc files and not the .h files. It appears to me as if it only shows me the other uses but not the definition, which is obviously a problem.
I also tried generating the ctags myself and changing the command options in the settings of the package, unfortunately without any success.
Atoms built-in symbols-view
In order to get this to work, one needs to generate the symbols. This can be, for example, achieved with the symbol-gen package. However, it shows me some of the definitions, but also no .h files. Moreover, jumping to the definition results in a Selected file does not exist., therefore it is not usable at all.
goto-definition
Just for completeness, there is also this package. It does not work for me, since c++ is not supported but maybe others will find it useful.
symbols-plus
Again, for completeness, this should be a replacement for the atom built-in, but when disabling the build-in it does not show me any jump functionality nor is a short cut mentioned.
So, basically, nothing really works well. I have tried Symbol Tree View but it but barely works.

How to print in REPL the code of functions in Julia?

In Julia, a lot of the Base and closer related functions are also written in pure Julia, and the code is easily avaible. One can skim through the repository or the local downloaded files, and see how the function is written/implemented. But I think there is allready some built in method that does that for you, so you can write in REPL or Jupyter Notebook something like:
#code functioninquestion()
and get something like:
functioninquestion(input::Type)
some calculations
return
end
without pagingh throug the code.
I just don't remember the method or call. I have read the Reflection/Introspection section of the Manual but I cannot seem to be able to use anything there. I've tried methods, methodswith, code_lowered, expand and cannot seem to make them give what I want-
This is not currently supported but probably will be in the future.
Though this may not be what the OP is looking for, #less is very convenient to read the underlying code (so I very often use it). For example,
julia> #less 1 + 2
gives
+(x::Int, y::Int) = box(Int,add_int(unbox(Int,x),unbox(Int,y)))
which corresponds to the line given by
julia> #which 1 + 2
+(x::Int64, y::Int64) at int.jl:8
#edit functioninquestion() will open up your editor to the location of the method given.
It probably wouldn't be to hard to take the same information used by #edit and use it to open the file and skip to the method definition, and then display it directly in the REPL (or Jupyter).
EDIT: While I was answering, somebody else mentioned #less, which seems to do exactly what you want already.
There is now another tool for this, https://github.com/timholy/CodeTracking.jl. It is part of Revise.jl (and works better when also using Revise). It should work inside Jupyter and with functions defined in the REPL, unlike #edit/#less.

Adding a function in R for use without loading it

So I have code for a custom function in R, e.g. simply:
f <- function(x) return(x)
What I want to do is be able to call this function f as if it came with default R. That is, I don't want to have to source() the file containing the code to be able to use the function. Is there a way to accomplish this?
What you are looking to do is documented extensively under ?Startup. Basically, you need to customize your Rprofile.site or .Rprofile to include the functions that you want available on startup. A simple guide can be found at the Quick-R site.
One thing to note: if you are commonly sharing code with others, you do need to remember what you've changed in your startup options and be sure that the relevant functions are also shared.

plot.predict() or predict.plot() functions cited in literature, but no longer exists

I am trying to use predict.plot or plot.predict (I've seen both of them referenced on various websites and I don't know which one is right).
However, in R, neither of these are valid functions. I don't know if I'm missing a package or if the sources I'm using are outdated in terms of the functions being referenced.
This site is using the function
It's very old. Can someone familiar with stats help me figure out how to do this with the latest version of R, or help me figure out how to get predict.plot/plot.predict to work?
This is a user defined function. The author of the course you linked to provides it online:
Link to R script
The S3 dispatch system for functions in R examines the class of the first argument and then calls a function with the name func.class. In this case the author has defined several plot.predict functions: predict.plot.data.frame, predict.plot.lm, and predict.plot.formula which are then given the arguments on hte basis of the class of what is (first) in the argument list. The plot.predict function is just this:
predict.plot <- function(object, ...) UseMethod("predict.plot")
The "good stuff" is in the other three functions at the link Roland provided. I do think the author's use of a dot in the name for the generic function is a bit confusing. One might have expected there to be a class "plot" for which there was a generic function predict, but that is not really the case here, although you might find it interesting to just type: methods(predict) .After you had loaded the R script on that website you could find those various functions using:
methods(predict.plot)
#[1] predict.plot.data.frame predict.plot.formula predict.plot.lm

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