how to break a line in RStudio - rstudio

New to R, and have trouble with RStudio but not with R GUI when typing a long code.
R GUI allows me to break the line of code when pressing Enter by adding +
e.g.
>rolldice <- function (){
+ dice <-1:6
+ rolldice <- sample (x=dice, size=2)
+ sum (rolldice)
}
However, in RStudio, it autocompletes part of the code when I try something like below
>rolldice <-function (){}
I tried to add additional codes within the bracket but somehow could not break the line by Enter. Enter would end the function, not adding additional lines with +. Thus I am stuck with either
(when not pressing Enter)
>rolldice <- function (){dice<1:6 rolldice <- sample(x=dice, size=2) sum(rolldice)}
which is considered an error code by RStudio
or
when pressing Enter to attempt to create a line breaker, which gives me the following
>rolldice <- function (){}
>
Surprisingly googling this (e.g. RStudio line breaker) did not yield any solution. One suggestion was to add n , but I have no clue what n is (obviously I tried the alphabet, but it was wrong).
I know I must have missed some piece of relevant info on the internet or in a book, since this is one of the most rudimentary issues in learning a new language.
Any help?

Related

R- debug: line by line through a loop

I try to find a way to debug through R studio, however all the solutions I can find do not really work.
1.) CTRL+enter: works but does not go through every iteration of the loop but only once.
2.) Adding "browser()" stops at that point but I am not able to go from there line by line (neither "n" nor "F10" works?
Any idea what the issue could be?
Put the code/script inside a function:
function_to_debug <- function(data){
a = 2+3
return(a)
}
Then run this in R console:
debug(function_to_debug)
The debugger starts and you can step through each line of the function.

rxCrossTabs crashes on a character variable

When I run this in Revolution R Enterprise, it totally crashes Rstudio on the last line:
require(RevoScaleR)
set.seed(1)
a = sample(c("happy", "sad", "other", NA), 100, replace = TRUE)
y = data.frame(a)
y$a = as.character(y$a)
rxCrossTabs(1 ~ a, data = y)
This seems buggy to me. Shouldn't it at least throw a warning and return me the command prompt?
The quick fix above is to simply exclude the line y$a = as.character(y$a), but I'd rather really understand what is going on. I'm having the same sort of crash with rxCrossTabs when I try to run it on a .xdf file, and I wonder if it is a related issue. I.e., perhaps somehow R is reading in a column of the file as character only instead of as factor, but I'm not sure how to investigate that directly.
This is not a Revolution R problem; it's an Rstudio problem. If I run your code in R in a terminal session, it does not crash, but it does throw an error message that Rstudio should have relayed to you:
Evidently your challenge now is to figure out how to put the right variable type on each column of interest in your .xdf file. Specifically, you need to have a factor variable to use the rxCrossTabs function.

How to program faster, (generate code from a pattern?)

I frequently run into problems that could be solved with automating code writing, but aren't long enough to justify it as tediously entering each piece is faster.
Here is an example:
Putting lists into dictionaries and things like this. Converting A into B.
A
hotdog HD
hamburger HB
hat H
B
def symbolizeType
case self.type
when "hotdog"
return "HD"
when "hamburger"
return "HB"
when "hat"
return "H"
end
Sure I could come up with something to do this automatically, but it would only make sense if the list was 100+ items long. For a list of 10-20 items, is there a better solution than tediously typing? This is a Ruby example, but I typically run into cases like this all the time. Instead of a case statement, maybe it's a dictionary, maybe it's a list, etc.
My current solution is a python template with the streaming input and output already in place, and I just have to write the parsing and output code. This is pretty good, but is there better? I feel like this would be something VIM macro would excel at, but I'm that experienced with VIM. Can VIM do this easily?
For vim, it'd be a macro running over a list of space separated pairs of words, inserting the first 'when "' bit, the long form word 'hotdog', the ending quote, a newline and 'return "', and then the abbreviation and then final quote, then going back to the list and repeating.
Starting with a register w of:
when "
register r of:
return "
an initial list of:
hotdog HD
hamburger HB
hat H
and a starting file of:
def symbolizeType
case self.type
"newline here"
you can use the following macro at the start of the initial list:
^"ayeeeb"byeo"wp"apa"^Mrb"j
where ^M is a newline.
I do this frequently, and I use a single register and a macro, so I'll share.
Simply pick a register, record your keystrokes, and then replay your keystrokes from the register.
This is a long explanation, but the process is extremely simple and intuitive.
Here are the steps that I would take:
A. The starting text
hotdog HD
hamburger HB
hat H
B. Insert the initial, non-repetitive lines preceding the text to transform
def symbolizeType
case self.type
hotdog HD
hamburger HB
hat H
C. Transform the first line, while recording your keystrokes in a macro
This step I'll write out in detailed sub-steps.
Place the cursor on the first line to transform ("hotdog") and type qa to begin recording your keystrokes as a macro into register a.
Type ^ to move the cursor to the start of the line
Type like you normally would to transform the line to what you want, which for me comes out looking like the following macro
^i^Iwhen "^[ea"^[ldwi^M^Ireturn "^[ea"^[j
Where ^I is Tab, ^[ is Esc, and ^M is Enter.
After the line is transformed to your liking, move your cursor to the next line that you want to transform. You can see this in the macro above with the final j at the end.
This will allow you to automatically repeat the macro while it cycles through each repetitive line.
Stop recording the macro by typing q again.
You can then replay the macro from register a as many times as you like using a standard vim count prefix, in this case two consecutive times starting from the next line to transform.
2#a
This gives the following text
def symbolizeType
case self.type
when "hotdog"
return "HD"
when "hamburger"
return "HB"
when "hat"
return "H"
D. Finally, insert the ending non-repetitive text
def symbolizeType
case self.type
when "hotdog"
return "HD"
when "hamburger"
return "HB"
when "hat"
return "H"
end
Final Comments
This works very quick for any random, repetitive text, and I find it very fluent.
Simply pick a register, record your keystrokes, and then replay your keystrokes from the register.
For things like this I have a few ways of making it easier. One is to use an editor like Sublime Text that allows you to multi-edit a number of things at once, so you can throw in markup with a few keystrokes and convert that into a Hash like:
NAME_TO_CODE = {
hotdog: 'HD',
hamburger: 'HB',
hat: 'H'
}
Not really a whole lot changed there. Your function looks like:
def symbolize_type(type)
NAME_TO_CODE[type.to_sym]
end
Defining this as a data structure has the bonus of being able to manipulate it:
CODE_TO_NAME = NAME_TO_CODE.invert
Now you can do this:
def unsymbolize_type(symbol)
CODE_TO_NAME[symbol.to_s]
end
You can also get super lazy and just parse it on the fly:
NAME_TO_CODE = Hash[%w[
hotdog HD
hamburger HB
hat H
].each_slice(2).to_a]
snippets are like the built-in :abbreviate on steroids, usually with parameter insertions, mirroring, and multiple stops inside them. One of the first, very famous (and still widely used) Vim plugins is snipMate (inspired by the TextMate editor); unfortunately, it's not maintained any more; though there is a fork. A modern alternative (that requires Python though) is UltiSnips. There are more, see this list on the Vim Tips Wiki.
There are three things to evaluate: First, the features of the snippet engine itself, second, the quality and breadth of snippets provided by the author or others; third, how easy it is to add new snippets.

event.which value 'incorrect'

I get the "incorrect" value for event.which in chrome. for example:
$(document).keypress(function (e) {
alert(String.fromCharCode(e.which));
alert(e.which);
});
this code produces two alerts when I press the numpad '+' key, first says k, second says 107.
I want the first one to say + and the second, well the second doesn't matter too much, all I care about is getting the + symbol when typing the + key. Same for all mathematical operators, I am writing a calculator and need those symbols correct for the input elements. How do I do it?
---- WORKING ----
I must have done something wrong before, now it works great...
Try using .keydown instead , i had few issues earlier with keypress behaviour in chrome which got resolved when I used keydown

Reformatting text (or, better, LaTeX) in 80 colums in SciTE

I recently dived into LaTeX, starting with the help of a WYSIWYM editor like Lix. Now I'm staring writing tex files in Sci-TE, It already has syntax higlighting and I adapted the tex.properties file to work in Windows showing a preview on Go [F5]
One pretty thing Lyx does, and it's hard to acheive with a common text editor, is to format text in 80 columns: I can write a paragraph and hit Return each time I reach near the edge column but if, after the first draft, I want to add or cut some words here and there I end up breaking the layout and having to rearrange newlines.
It would be useful to have a tool in Sci-TE so I can select a paragraph of text I added or deleted some words in and have it rearranged in 80 columns. Probably not something working on the whole document since it could probably break some intended anticipated line break.
Probably I could easily write a Python plugin for geany, I saw vim has something similar, but I'd like to know if its' possible in Sci-TE too.
I was a bit disappointed when I found no answer as I was searching for same. No helpers by Google either, so I searched for Lua examples and syntax in a hope to craft it myself. I don't know Lua so this can perhaps be made differently or efficiently but its better then nothing I hope - here is Lua function which needs to be put in SciTE start-up Lua script:
function wrap_text()
local border = 80
local t = {}
local pos = editor.SelectionStart
local sel = editor:GetSelText()
if #sel == 0 then return end
local para = {}
local function helper(line) table.insert(para, line) return "" end
helper((sel:gsub("(.-)\r?\n", helper)))
for k, v in pairs(para) do
line = ""
for token in string.gmatch(v, "[^%s]+") do
if string.len(token .. line) >= border then
t[#t + 1] = line
line = token .. " "
else
line = line .. token .. " "
end
end
t[#t + 1] = line:gsub("%s$", "")
end
editor:ReplaceSel(table.concat(t, "\n"))
editor:GotoPos(pos)
end
Usage is like any other function from start-up script, but for completness I'll paste my tool definition from SciTE properties file:
command.name.8.*=Wrap Text
command.mode.8.*=subsystem:lua,savebefore:no,groupundo
command.8.*=wrap_text
command.replace.selection.8.*=2
It does respect paragraphs, so it can be used on broader selection, not just one paragraph.
This is one way to do it in scite: first, add this to your .SciTEUser.properties (Options/Open User Options file):
# Column guide, indicates long lines (https://wiki.archlinux.org/index.php/SciTE)
# this is what they call "margin line" in gedit (at right),
# in scite, "margin" is the area on left for line numbers
edge.mode=1
edge.column=80
... and save, so you can see a line at 80 characters.
Then scale the scite window, so the text you see is wrapped at the line.
Finally, select the long line text which is to be broken into lines, and do Edit / Paragraph / Split (for me the shortcut Ctrl-K also works for that).
Unfortunately, there seems to be no "break-lines-as-you-type" facility in scite, like the "Line Breaking" facility in geany. not anymore, now there's a plugin - see this answer
Well, I was rather disappointed that there seems to be no "break-lines-as-you-type" facility in scite; and I finally managed to code a small Lua plugin/add-on/extension for that, and released it here:
lua-users wiki: Scite Line Break
Installation and usage instructions are in the script itself. Here is how SciTE may look when the extension properly installed, and toggle activated after startup:
Note that it's pretty much the same functionality as in geany - it inserts linebreaks upon typing text - but not on pressing backspace, nor upon copy/pasting.
the same but more easy, I think...
put this in the user properties:
command.name.0.*=swrap
command.0.*=fold -s $(FileNameExt) > /tmp/scite_temp ; cat /tmp/scite_temp >$(FileNameExt)
command.is.filter.0.*=1
Ciao
Pietro

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