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Order data frame rows according to vector with specific order
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I prefer to use ***_join in dplyr whenever I need to match data. One possible try for this
left_join(data.frame(name=target),df,by="name")
Note that the input for ***_join require tbls or data.frame
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What are the differences between Autotools, Cmake and Scons?
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In truth, Autotools' only real 'saving grace' is that it is what all the GNU projects are largely using.
Issues with Autotools:
Truly ARCANE m4 macro syntax combined with verbose, twisted shell scripting for tests for "compatibility", etc.
If you're not paying attention, you will mess u...
switch case statement error: case expressions must be constant expression
...instead of an if-else:
private enum LayoutElement {
NONE(-1),
PLAY_BUTTON(R.id.playbtn),
STOP_BUTTON(R.id.stopbtn),
MENU_BUTTON(R.id.btnmenu);
private static class _ {
static SparseArray<LayoutElement> elements = new SparseArray<LayoutElement>();
}
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How to tell git to ignore individual lines, i.e. gitignore for specific lines of code [duplicate]
...o be filtered:
*.rb filter=gitignore, i.e. run filter named gitignore on all *.rb files
Define the gitignore filter in your gitconfig:
$ git config --global filter.gitignore.clean "sed '/#gitignore$/d'", i.e. delete these lines
$ git config --global filter.gitignore.smudge cat, i.e. do nothing ...
How to check version of a CocoaPods framework
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The Podfile.lock keeps track of the resolved versions of each Pod installed. If you want to double check that FlurrySDK is using 4.2.3, check that file.
Note: You should not edit this file. It is auto-generated when you run pod install or pod update
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In Vim, is there a way to paste text in the search line?
I want to search for $maximumTotalAllowedAfterFinish and replace it with $minimumTotalAllowedAfterFinish . Instead of typing the long text:
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How to change the default collation of a table?
creates a table with the default collation latin1_general_ci ;
4 Answers
4
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What is the difference between Debug and Release in Visual Studio?
... result some lines of your code might get left without any instructions at all, or some might get all mixed up. Step-by-step debugging would be impossible. Also, local variables are often optimized in mysterious ways, so Watches and QuickWatches often don't work because the variable is "optimized aw...
Difference between Math.Floor() and Math.Truncate()
...seems, simply because it can round to a specific number of decimal places. All the others round to zero decimals always. For example:
n = 3.145;
a = System.Math.Round (n, 2, MidpointRounding.ToEven); // 3.14
b = System.Math.Round (n, 2, MidpointRounding.AwayFromZero); // 3.15
With the other...
How to generate the JPA entity Metamodel?
...etamodel Generator jar in the classpath and compiler level>=1.6 that is all you need build the project and metamodel will be generated automatically.
In case of IDE Eclipse
1. goto Project->Properties->Java Compiler->Annotation Processing and enable it.
2. Expand Annotation Processing...