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Scala how can I count the number of occurrences in a list
...", "banana", "apple", "oranges", "oranges")
s.groupBy(identity).mapValues(_.size)
giving a Map with a count for each item in the original sequence:
Map(banana -> 1, oranges -> 3, apple -> 3)
The question asks how to find the count of a specific item. With this approach, the solution w...
Why use Ruby's attr_accessor, attr_reader and attr_writer?
...write classes which will work correctly no matter how their public API is called.
class Person
attr_accessor :age
...
end
Here, I can see that I may both read and write the age.
class Person
attr_reader :age
...
end
Here, I can see that I may only read the age. Imagine that it is set ...
std::unique_lock or std::lock_guard?
...er you need to relock the guard.
std::unique_lock has other features that allow it to e.g.: be constructed without locking the mutex immediately but to build the RAII wrapper (see here).
std::lock_guard also provides a convenient RAII wrapper, but cannot lock multiple mutexes safely. It can be us...
Bin size in Matplotlib (Histogram)
...width in this example could be found by: (data.max() - data.min()) / number_of_bins_you_want. The + binwidth could be changed to just 1 to make this a more easily understood example.
– Jarad
Jan 22 '18 at 17:31
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Hidden Features of MySQL
...
Since you put up a bounty, I'll share my hard won secrets...
In general, all the SQLs I tuned today required using sub-queries. Having come from Oracle database world, things I took for granted weren’t working the same with MySQL. And my reading on MySQL tuning makes me conclude that MySQL is be...
Java 8 forEach with index [duplicate]
... way to build a forEach method in Java 8 that iterates with an index? Ideally I'd like something like this:
3 Answers
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JavaScript is in array
...if the result > -1 and false if result === -1
– bm_i
Nov 5 '12 at 19:01
11
@bm_i Which faster?...
How do I use vim registers?
...on Windows (or from "mouse highlight" clipboard on Linux)
"*p
To access all currently defined registers type
:reg
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In Python script, how do I set PYTHONPATH?
... that if you want to make sure that Python checks the new directory before all of the others when importing, you should put the new directory first in the list, as in sys.path.insert(0, '/path/to/whatever').
– wecsam
Jun 15 '17 at 16:22
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Parse JSON in C#
...lizeObject(object o);
This are already part of Json.NET so you can just call them on the JsonConvert class.
Link: Serializing and Deserializing JSON with Json.NET
Now, the reason you're getting a StackOverflow is because of your Properties.
Take for example this one :
[DataMember]
public st...