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dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
...e to go with @Moody_Mudskipper's answer: Using .drop=FALSE can give potentially unexpected results when one or more grouping variables are not coded as factors. See examples below:
library(dplyr)
data(iris)
# Add an additional level to Species
iris$Species = factor(iris$Species, levels=c(levels(ir...
How do I get a consistent byte representation of strings in C# without manually specifying an encodi
How do I convert a string to a byte[] in .NET (C#) without manually specifying a specific encoding?
40 Answers
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How to make code wait while calling asynchronous calls like Ajax [duplicate]
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Use callbacks. Something like this should work based on your sample code.
function someFunc() {
callAjaxfunc(function() {
console.log('Pass2');
});
}
function callAjaxfunc(callback) {
//All ajax calls called here
o...
Resolving LNK4098: defaultlib 'MSVCRT' conflicts with
...ne. Note how these libraries are not mentioned here. The linker automatically figures out what /M switch was used by the compiler and which .lib should be linked through a #pragma comment directive. Kinda important, you'd get horrible link errors and hard to diagnose runtime errors if there was a...
What is the difference between Elastic Beanstalk and CloudFormation for a .NET project?
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They're actually pretty different. Elastic Beanstalk is intended to make developers' lives easier. CloudFormation is intended to make systems engineers' lives easier.
Elastic Beanstalk is a PaaS-like layer ontop of AWS's IaaS services ...
git - merge conflict when local is deleted but file exists in remote
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You should resolve the conflicts as you see fit. If the file really is supposed to be removed, and you will be publishing that change to origin, remove it again:
git rm path/to/file
If the file should in fact be tracked still, add it (the version in the work tree will be the version f...
Reference: Comparing PHP's print and echo
...hat while they appear to users as two distinct constructs, they are both really shades of echo if you get down to basics, i.e. look at the internal source code. That source code involves the parser as well as opcode handlers. Consider a simple action such as displaying the number zero. Whether you ...
Global variables in AngularJS
...lue. The problem with it is that the controller that initialises it, gets called again by angular some how and then resets the variable back to its initial value.
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Is it safe to ignore the possibility of SHA collisions in practice?
...rgued that any unlucky event with a probability lower than that is not actually very important.
If we have a "perfect" hash function with output size n, and we have p messages to hash (individual message length is not important), then probability of collision is about p2/2n+1 (this is an approximat...
Force drop mysql bypassing foreign key constraint
I'm trying to delete all tables from a database except one, and I end up having the following error:
6 Answers
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