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How does one reorder columns in a data frame?
... has four columns like so df[,c(1,2,3,4)].
Note the first comma means keep all the rows, and the 1,2,3,4 refers to the columns.
To change the order as in the above question do df2[,c(1,3,2,4)]
If you want to output this file as a csv, do write.csv(df2, file="somedf.csv")
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Difference between Activity Context and Application Context
...nformation about the current activity that is necessary to complete those calls. If you show the exact error message, might be able to point to what exactly it needs.
But in general, use the activity context unless you have a good reason not to.
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How to make links in a TextView clickable?
...ot
// respond to user input. To make them active, you need to
// call setMovementMethod() on the TextView object.
TextView t2 = (TextView) findViewById(R.id.text2);
t2.setMovementMethod(LinkMovementMethod.getInstance());
I removed most of the attributes on my TextView to match wh...
How does the compilation/linking process work?
... #include directives with the content of the respective files (which is usually just declarations), doing replacement of macros (#define), and selecting different portions of text depending of #if, #ifdef and #ifndef directives.
The preprocessor works on a stream of preprocessing tokens. Macro subs...
Bootstrap 3 and 4 .container-fluid with grid adding unwanted padding
...anks a bunch. I'd like to remove it when I'm using a column, though. I really don't want to mess with the core bootstrap css. I suspect there must be a sanctioned way to do this. Any thoughts?
– Tim
Aug 22 '14 at 13:22
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How can I unstage my files again after making a local commit?
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What is described in this answer is actually what git commit --amend does; but with a much more complicated workflow. This does not answer the question OP asked, in spite of giving a good direction (git reset).
– 7heo.tk
May 1...
An algorithm for inflating/deflating (offsetting, buffering) polygons
...re written in Delphi, C++ and C#. It has a very unencumbered Boost license allowing it to be used in both freeware and commercial applications without charge.
Polygon offsetting can be performed using one of three offset styles - squared, round and mitered.
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Class with single method — best approach?
...lity either before or after the old method, we can create a new class and call the old one inside of it - but that's just gross.
Interface woes
Static methods cannot be defined through interfaces for logic reasons. And since we can't override static methods, static classes are useless when we need ...
Virtual functions and performance - C++
...e a very slight effect on performance, but it's unlikely to affect the overall performance of your application. Better places to look for performance improvements are in algorithms and I/O.
An excellent article that talks about virtual functions (and more) is Member Function Pointers and the Fastes...
Compiling C++ on remote Linux machine - “clock skew detected” warning
I'm connected to my university's small Linux cluster via PuTTY and WinSCP, transferring files using the latter and compiling and running them with the former. My work so far has been performed in the university's labs, but today I have been doing some work at home that generated an interesting warn...