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Filter rows which contain a certain string
...:
dplyr::filter(df, !grepl("RTB",TrackingPixel))
Since you have not provided the original data, I will add a toy example using the mtcars data set. Imagine you are only interested in cars produced by Mazda or Toyota.
mtcars$type <- rownames(mtcars)
dplyr::filter(mtcars, grepl('Toyota|Mazda', ...
adding noise to a signal in python
...
# covers 95.4% of the dataset.
# Since, anomalies are considered to be rare and typically within the
# 5-10% of the data; this filtering
# technique might work
#for us(https://en.wikipedia.org/wiki/68%E2%80%9395%E2%80%9399.7_rule)
indexes_furhter_aw...
git stash blunder: git stash pop and ended up with merge conflicts
I did a git stash pop and ended up with merge conflicts. I removed the files from the file system and did a git checkout as shown below, but it thinks the files are still unmerged. I then tried replacing the files and doing a git checkout again and same result. I event tried forcing it with -...
Apache Spark: map vs mapPartitions?
...ons)? Does it move data between nodes? I've been using mapPartitions to avoid moving data between nodes, but wasn't sure if flapMap would do so.
– Nicholas White
Jan 18 '14 at 10:52
...
What is data oriented design?
...is:
class Ball {
Point position;
Color color;
double radius;
void draw();
};
And then you would create a collection of balls like this:
vector<Ball> balls;
Data Oriented Approach
In Data Oriented Design, however, you are more likely to write the code like this:
class Balls {...
Can Java 8 code be compiled to run on Java 7 JVM?
...ava 8 features in the code I write for quite some time, since I want to avoid people having to upgrade their local Java installation.
– JesperE
Aug 15 '14 at 10:05
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Changing names of parameterized tests
... fInput= input;
fExpected= expected;
}
@Test
public void testFib() {
assertEquals(fExpected, fib(fInput));
}
private int fib(int x) {
// TODO: actually calculate Fibonacci numbers
return 0;
}
}
will give names like testFib[1: fib(1)=1] and ...
val-mutable versus var-immutable in Scala
Are there any guidelines in Scala on when to use val with a mutable collection versus using var with an immutable collection? Or should you really aim for val with an immutable collection?
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Why should I use core.autocrlf=true in Git?
...
The only specific reasons to set autocrlf to true are:
avoid git status showing all your files as modified because of the automatic EOL conversion done when cloning a Unix-based EOL Git repo to a Windows one (see issue 83 for instance)
and your coding tools somehow depends on a nati...
One DbContext per web request… why?
... echoing Ian: Having a single DbContext for the whole application is a Bad Idea. The only situation where this makes sense is when you have a single-threaded application and a database that is solely used by that single application instance. The DbContext is not thread-safe and and since the DbConte...