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Changing column names of a data frame
... Thank you. I think this is somehow annoying with R: Why is it so difficult to change the column name if you do not want to use the index number but the old name :(
– Arne
Mar 18 '14 at 14:41
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CSS: how to add white space before element's content?
...the text-indent property.
p { text-indent: 1em; }
JSFiddle demo
Edit:
If you want the space to be colored, you might consider adding a thick left border to the first letter. (I'd almost-but-not-quite say "instead", because the indent can be an issue if you use both. But it feels dirty to me t...
How to list all the files in a commit?
...d Way (because it's a plumbing command; meant to be programmatic):
$ git diff-tree --no-commit-id --name-only -r bd61ad98
index.html
javascript/application.js
javascript/ie6.js
Another Way (less preferred for scripts, because it's a porcelain command; meant to be user-facing)
$ git show --pretty...
How to succinctly write a formula with many variables from a data frame?
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There is a special identifier that one can use in a formula to mean all the variables, it is the . identifier.
y <- c(1,4,6)
d <- data.frame(y = y, x1 = c(4,-1,3), x2 = c(3,9,8), x3 = c(4,-4,-2))
mod <- lm(y ~ ., data = d)
You can also d...
Differences between “java -cp” and “java -jar”?
What is the difference between running a Java application with java -cp CLASSPATH and java -jar JAR_FILE_PATH ? Is one of them preferred to the other for running a Java application? I mean which one of these ways is more expensive for JVM (according to their machine resources usage)?
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Is it not possible to stringify an Error using JSON.stringify?
...using web sockets. I can replicate the issue I am facing using JSON.stringify to cater to a wider audience:
10 Answers
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Using .gitignore to ignore everything but specific directories
...u have to explicitly allow content for each level you want to include. So if I have subdirectories 5 deep under themes, I still need to spell that out.
This is only how it worked for me. If someone cares to offer a more informed explanation by all means.
Also, these answers helpful:
how-do-nega...
How to use WinForms progress bar?
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I would suggest you have a look at BackgroundWorker. If you have a loop that large in your WinForm it will block and your app will look like it has hanged.
Look at BackgroundWorker.ReportProgress() to see how to report progress back to the UI thread.
For example:
private voi...
Are SVG parameters such as 'xmlns' and 'version' needed?
...nts (browsers) ignore the version attribute, so you can always drop that.
If you embed your SVG inline in a HTML page and serve that page as text/html then xmlns attributes are not required. Embedding SVG inline in HTML documents is a fairly recent innovation that came along as part of HTML5.
If h...
How can I return an empty IEnumerable?
...wing code and the suggestions given in this question , I've decided to modify this original method and ask if there are any values in the IEnumarable return it, if not return an IEnumerable with no values.
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