Colour for R code chunk in listings package - r

I wish to insert a R code chunk in a LaTeX document. The default settings for the listings package also changes the font, but not the colour, which I need.
Although I understand that I can set the colours using the lstset function, I am not very sure of the combination that would look good. Thus, can anyone share their lstset settings for the listings package to colour R syntax? This way everyone who sees this post can use the same settings!

\documentclass[12pt]{article}
\usepackage{listings}
\usepackage[usenames,dvipsnames]{color}
\lstset{
language=R, % the language of the code
basicstyle=\tiny\ttfamily, % the size of the fonts that are used for the code
numbers=left, % where to put the line-numbers
numberstyle=\tiny\color{Blue}, % the style that is used for the line-numbers
stepnumber=1, % the step between two line-numbers. If it is 1, each line
% will be numbered
numbersep=5pt, % how far the line-numbers are from the code
backgroundcolor=\color{white}, % choose the background color. You must add \usepackage{color}
showspaces=false, % show spaces adding particular underscores
showstringspaces=false, % underline spaces within strings
showtabs=false, % show tabs within strings adding particular underscores
frame=single, % adds a frame around the code
rulecolor=\color{black}, % if not set, the frame-color may be changed on line-breaks within not-black text (e.g. commens (green here))
tabsize=2, % sets default tabsize to 2 spaces
captionpos=b, % sets the caption-position to bottom
breaklines=true, % sets automatic line breaking
breakatwhitespace=false, % sets if automatic breaks should only happen at whitespace
keywordstyle=\color{RoyalBlue}, % keyword style
commentstyle=\color{YellowGreen}, % comment style
stringstyle=\color{ForestGreen} % string literal style
}
\begin{document}
\begin{lstlisting}
library(foreign)
foo <- rnorm(100)
# writing a function
bar <- apply(foo, 1, function(x){
y <- sqrt(x)
cat(paste('The result is ', x )))
})
bar
str(bar)
foo + bar
\end{lstlisting}
\end{document}

Related

Control line spacing in unordered list in R Markdown

I am creating a html report using R Markdown. The first paragraph contains a list of categories represented by certain samples with short descriptions. Here is an example:
This is the test list:
* **first group**:
+ **item 1** - this is the description of an item
* **second group**:
+ **item 2** - this is the description of an item
+ **item 3** - this is the description of an item
* **third group**:
+ **item 4** - this is the description of an item
* **fourth group**:
+ **item 5** - this is the description of an item
+ **item 6** - this is the description of an item
The text was inserted outside the code chunks. I would like to preserve this (even) spacing between the lines in knitted document, so it would be easy readable. Otherwise it looks too squished. Unfortunately R Markdown changes spacing, so some of them are uneven. I tried using trailing spaces and defining line breaks with br, but nothing changed. I could off course edit the html file manually after knitting, but this is a brute force way. R Markdown has to have some option to deal with it - but I was not able to figure it out myself. Would appreciate any help.
You could add a css tag at the start of your rmarkdown document to specify how you would like the html output to interpret line heights:
```{css}
li {
line-height: 3;
}
...

How to add a line in the pdf generated pdf by `exams` using the `exams2nops`?

We are generating a pdf through exams2nops using the items in blocks of choice, we would like to delimitate the blocks in the PDF adding a horizontal line after the last exercise of each block. Having that in mind we added a ***, ---, <hr/> however the behavior was always the same:
I would like a single line without adding the exercise number that's next in the exam:
It is not so easy to solve this by putting the horizontal line into the exercise file. The reason is that the line is needed after the answerlist but the answerlist is not formatted in the exercise but by exams2nops.
A workaround is to tweak the definition of the {question} environment in the LaTeX template used by exams2nops. By default this is simply:
\newenvironment{question}{\item}{}
Where \item is executed at the beginning of the {question} and nothing at the end of it. Changing this by
\renewenvironment{question}{\item}{\hrulefill}
would insert a horizontal line after every question. If you just want it after selected questions you need to insert if/else statements for certain enumerated items. For example, for inserting the horizontal rule after the second item only, you can redefine:
\renewenvironment{question}{\item}{\ifnum\value{enumi}=2 {\hrulefill} \else {} \fi}
Thus, you get the enumi counter from the {enumerate} environment that you use and compare it with 2. If true, you insert the horizontal line, and otherwise you do nothing.
Adding escapes for the backslashes you can pass this re-definition to exams2nops through the header argument:
exams2nops(c("swisscapital", "switzerland", "tstat2", "deriv2"),
header = "\\renewenvironment{question}{\\item}{\\ifnum\\value{enumi}=2 {\\hrulefill} \\else {} \\fi}")
The resulting output is:

how to put y axis greek letters in Veusz plot?

I want to put Capitalomega with index DE and k label:
and then ı want to show on the y axis label? How to do them?
Generally you can use tex symbols in Veusz. Therefore, you can write \Omega_{DE} and \Omega_{k} for your request. See details here (Sec. 2.4 Text).
Veusz understands a limited set of LaTeX-like formatting for text. There are some differences (for example, "10^23" puts the 2 and 3 into superscript), but it is fairly similar. You should also leave out the dollar signs. Veusz supports superscripts ("^"), subscripts ("_"), brackets for grouping attributes are "{" and "}".
Supported LaTeX symbols include: \AA, \Alpha, \Beta, \Chi, \Delta, \Epsilon, \Eta, \Gamma, \Iota, \Kappa, \Lambda, \Mu, \Nu, \Omega, \Omicron, \Phi, \Pi, \Psi, \Rho, \Sigma, \Tau, \Theta, \Upsilon, \Xi, \Zeta, \alpha, \approx, \ast, \asymp, \beta, \bowtie, \bullet, \cap, \chi, \circ, \cup, \dagger, \dashv, \ddagger, \deg, \delta, \diamond, \divide, \doteq, \downarrow, \epsilon, \equiv, \eta, \gamma, \ge, \gg, \in, \infty, \int, \iota, \kappa, \lambda, \le, \leftarrow, \lhd, \ll, \models, \mp, \mu, \neq, \ni, \nu, \odot, \omega, \omicron, \ominus, \oplus, \oslash, \otimes, \parallel, \perp, \phi, \pi, \pm, \prec, \preceq, \propto, \psi, \rhd, \rho, \rightarrow, \sigma, \sim, \simeq, \sqrt, \sqsubset, \sqsubseteq, \sqsupset, \sqsupseteq, \star, \stigma, \subset, \subseteq, \succ, \succeq, \supset, \supseteq, \tau, \theta, \times, \umid, \unlhd, \unrhd, \uparrow, \uplus, \upsilon, \vdash, \vee, \wedge, \xi, \zeta. Please request additional characters if they are required (and exist in the unicode character set). Special symbols can be included directly from a character map.
Other LaTeX commands are supported. "\" breaks a line. This can be used for simple tables. For example "{a\b} {c\d}" shows "a c" over "b d". The command "\frac{a}{b}" shows a vertical fraction a/b.
Also supported are commands to change font. The command "\font{name}{text}" changes the font text is written in to name. This may be useful if a symbol is missing from the current font, e.g. "\font{symbol}{g}" should produce a gamma. You can increase, decrease, or set the size of the font with "\size{+2}{text}", "\size{-2}{text}", or "\size{20}{text}". Numbers are in points.
Various font attributes can be changed: for example, "\italic{some italic text}" (or use "\textit" or "\emph"), "\bold{some bold text}" (or use "\textbf") and "\underline{some underlined text}".
Example text could include "Area / \pi (10^{-23} cm^{-2})", or "\pi\bold{g}".
Veusz plots these symbols with Qt's unicode support. You can also include special characters directly, by copying and pasting from a character map application. If your current font does not contain these symbols then you may get a box character.
In addition to the answer OmG posted, you can also directly enter the character (via a character map application or copy and paste), as Veusz supports unicode characters.

Dynamic Rstudio Code Snippet

I tend to use a lot of line breaks in my code like the following:
# Data =========================================================================
Where the entire comment is always 80 characters long (including the hashtag). What I would like to do is write a code snippet for Rstudio that will insert the hashtag, then a space, then allow the user to type out a series of words, then insert another space, and finally fill in a bunch of "=" until the 80 character limit is reached.
I'm not familiar with how snippets work at all so I'm not sure how difficult this is.
I have this much:
snippet lb
# ${1:name}
but I have no idea how to add a dynamic number of "=" signs. Also, lb = linebreak.
You can't do this with snippets, unfortunately; a snippet is a text template that contains fixed text with slots for user-inserted text.
There is a command built into RStudio to do something very similar, however; from the Code menu, choose Insert Section (or Ctrl+Shift+R). This will do exactly what you're describing, with two small differences:
The line will extend to 5 characters before the print margin (you can adjust the print margin in Tools -> Global Options -> Code.
The line is composed of - rather than = characters.
One advantage to sections marked in this way is that you can use them to fold and navigate inside the file (look at the editor status bar after adding one).
You can use the rstudioapi (which can return column position) inside the snippet to get something like what you want.
Below is a snippet I use called endhead. I use it by commenting my header title and then applying the snippet, eg:
# Section name endhead
which results in:
# Section name -----------------------------------------------------------------
snippet endhead
`r paste0(rep.int("-", 88 - rstudioapi::primary_selection(rstudioapi::getActiveDocumentContext())$range$start[2]), collapse = "")`
You can write a snippet to manipulate text (somewhat). I wrote the snippet below to do something similar to what you want to do. I'm still ironing out the issues (just asked this question).
snippet comm
`r paste0(
"#######################################><###################\n## ",
date(),
" -------------------------------\n## ",
eval(
paste0(
gsub(
".{1,51}\\s?\\K\\b",
"\n## ",
gsub("\\.", " ", paste0(text)),
perl = T
)
)
),
"###################################><###################\n"
)`
I think if you write an R code snippet using an anonymous function that accepts text input via $$, counts the nchar in the text, calculates the number of -'s needed at the end, and then uses eval(paste0()) to insert the comment you should be able to make it work. I'll post a comment or answer here if I figure it out. Please do the same on my question if you get it to work. Thanks. (P.S. Go Badgers!)
Inspired by nick's answer above I designed two snippets that allow the user to choose what level section to insert.
The first will fill-in the rest of the line with #, =, or -.
snippet end
`r strrep(ifelse(substr("$$", 1, 1) %in% c("-", "="), substr("$$", 1, 1), "#"), 84 - rstudioapi::primary_selection(rstudioapi::getActiveDocumentContext())$range$start[2])`
Just specify the character you want to use after end (will default to # if nothing or any other character is given). For example:
## Level 1 Header end<shift+tab>
## Level 2 Header end=<shift+tab>
## Level 3 Header end-<shift+tab>
end<shift+tab>
end=<shift+tab>
end-<shift+tab>
Produces the following lines:
## Level 1 Header ##############################################################
## Level 2 Header =============================================================
## Level 3 Header -------------------------------------------------------------
################################################################################
===============================================================================
-------------------------------------------------------------------------------
Similarly to what Josh was suggesting, the following snippet uses th $$ notation to pass the text following the snippet as described here.
snippet !
`r paste("##", substr("$$", 4, nchar("$$")), strrep(substr("$$", 2, 2), 79-nchar("$$")))`
Again this allows user to select the section level (#, =, or -). The first character after !# should be the header level character you want followed by a space and the header text. For example:
!## Level 1 Header<shift+tab>
!#= Level 2 Header<shift+tab>
!#- Level 3 Header<shift+tab>
Produces the following lines:
## Level 1 Header ##############################################################
## Level 2 Header ==============================================================
## Level 3 Header --------------------------------------------------------------
I prefer the end snippet above because it is more robust and only allows the characters #, =, or - to be inserted where as ! will allow anything, but it is shorter and, I think, easier to understand than calls to the rstudioapi.
!loon<shift+tab>
## n ooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo

knitr displaying digits of an integer without scientific notation

when displaying a number with inline-code with more than four digits like
`r 21645`
the result in a knitted html-file is this: 2.164510^{4} (in reality inside the inline-hook there is a calculation going on which results in 21645). Even though I just want it to print the number, like so: 21645. I can easily fix this for one instance wrapping it inside as.integer or format or print, but how do I set an option for the whole knitr-document so that it prints whole integers as such (all I need is to print 5 digits)? Doing this by hand gets very annoying. Setting options(digits = 7) doesnt help. I am guessing I would have to set some chunk-optionor define a hook, but I have no idea how
I already solved it, just including the following line of code inside the setoptions-chunk in the beginning of a knitr document:
options(scipen=999)
resolves the issue, like one can read inside this answer from #Paul Hiemstra:
https://stackoverflow.com/a/25947542/4061993
from the documentation of ?options:
scipen: integer. A penalty to be applied when deciding to print
numeric values in fixed or exponential notation. Positive values bias
towards fixed and negative towards scientific notation: fixed notation
will be preferred unless it is more than scipen digits wider.
If you don't want to display scientific notation in this instance, but also don't want to disable it completely for your knitr report, you can use format() and set scientific=FALSE:
`r format(21645, scientific=FALSE)`
Note that if you type your numeric as integer it will be well formatted:
`r 21645L`
Of course you can always set an inline hook for more flexibility( even it is better to set globally options as in your answer):
```{r}
inline_hook <- function(x) {
if (is.numeric(x)) {
format(x, digits = 2)
} else x
}
knitr::knit_hooks$set(inline = inline_hook)
```

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