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Adding new column to existing DataFrame in Python pandas
... because if you have multiple rows, and you use the assignment, it assigns all rows of the new column with that value ( in your case e) which is usually undesirable.
– Paniz
Apr 27 '19 at 22:42
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What Automatic Resource Management alternatives exist for Scala?
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For now Scala 2.13 has finally supported: try with resources by using Using :), Example:
val lines: Try[Seq[String]] =
Using(new BufferedReader(new FileReader("file.txt"))) { reader =>
Iterator.unfold(())(_ => Option(reader.readLine()).ma...
How to convert ActiveRecord results into an array of hashes
...d objects to Ruby Hashes despite its name
tasks_records = TaskStoreStatus.all
tasks_records = tasks_records.as_json
# You can now add new records and return the result as json by calling `to_json`
tasks_records << TaskStoreStatus.last.as_json
tasks_records << { :task_id => 10, :sto...
List all base classes in a hierarchy of given class?
...ass Foo (whether it is a new-style class or not), how do you generate all the base classes - anywhere in the inheritance hierarchy - it issubclass of?
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Convert a row of a data frame to vector
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Might have been changed in the meantime, but today unlist allows dropping names: identical(unlist(df[1,], use.names = FALSE), as.numeric(df[1,])) (and btw df still is not a sensible name for a data.frame... ;-))
– Andri Signorell
Sep 25 '1...
Cosine Similarity between 2 Number Lists
... scientific routines for example, "routines for computing integrals numerically, solving differential equations, optimization, and sparse matrices." It uses the superfast optimized NumPy for its number crunching. See here for installing.
Note that spatial.distance.cosine computes the distance, and ...
Hash Map in Python
...res the keys to strings which are also valid Python identifiers (and internally, this also creates a dictionary).
– user395760
Jan 2 '12 at 17:31
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Principles for Modeling CouchDB Documents
...or instance). Managing the relationships or connections between various, smaller documents can be confusing at first, but CouchDB provides several options for combining disparate pieces into single responses.
The first big one is view collation. When you emit key/value pairs into the results of a m...
How to remove from a map while iterating it?
...= m.erase(it)" since C++11
}
else
{
++it;
}
}
Note that we really want an ordinary for loop here, since we are modifying the container itself. The range-based loop should be strictly reserved for situations where we only care about the elements. The syntax for the RBFL makes this clear...
How do I test an AngularJS service with Jasmine?
... problem is that the factory method, that instantiate the service, is not called in the example above (only creating the module doesn't instantiate the service).
In order to the service to be instantiated angular.injector has to be called with the module where our service is defined. Then, we can a...