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Apache Spark: map vs mapPartitions?
..."), 3)
val b = a.map(_.length)
val c = a.zip(b)
c.collect
res0: Array[(String, Int)] = Array((dog,3), (salmon,6), (salmon,6), (rat,3), (elephant,8))
mapPartitions
This is a specialized map that is called only once for each partition.
The entire content of the respective partitions is av...
How to create a MySQL hierarchical recursive query
... is only called to make sure this condition is always true, even if the pv string would for some reason yield a falsy value.
All in all, one may find these assumptions too risky to rely on. The documentation warns:
you might get the results you expect, but this is not guaranteed [...] the ord...
public friend swap member function
...ction is just noise. A member function allows for e.g. std::vector<std::string>().swap(someVecWithData);, which isn't possible with a swap free function because both arguments are passed by non-const reference.
– ildjarn
Apr 18 '11 at 1:34
...
OAuth 2.0: Benefits and use cases — why?
...o agree on the order of the arguments (so they're signing exactly the same string), and one of the main complaints about OAuth 1 is that it requires both the server and clients to sort and sign identically. This is fiddly code and either it's right or you get 401 Unauthorized with little help. This ...
ServiceStack vs ASP.Net Web API [closed]
...types are not converted and get written directly to the Response Stream:
String
Stream
IStreamWriter
byte[] - with the application/octet-stream Content Type.
An example of the Custom HTTP headers support can be seen by this CORS example where you can configure HTTP Headers globally or on a per-s...
What’s the difference between ScalaTest and Scala Specs unit test frameworks?
...ers by transforming them), precise failures, detailed differences for long strings, ...
Mockito has been given a nice BDD support in specs: Mockito
specs has DataTables which allow to group a lot of small example in a sort of table (if you can stand operators being used as the table delimiters)
In s...
Named colors in matplotlib
...r than a named color (apart from the fact that the hex code is passed as a string), and I will not include an image of the 16 million colors you can choose from...
For more details, please refer to the matplotlib colors documentation and the source file specifying the available colors, _color_dat...
Does PostgreSQL support “accent insensitive” collations?
...the function in the right expression. There you can also supply unaccented strings like 'Joao' directly.
The faster function does not translate to much faster queries using the expression index. That operates on pre-computed values and is very fast already. But index maintenance and queries not usi...
How do I tell Maven to use the latest version of a dependency?
...sion numbers - if you do not conform to a strict pattern Maven compares as strings and not numbers.
– Thorbjørn Ravn Andersen
Feb 25 '13 at 13:19
...
Replace Fragment inside a ViewPager
... ? fragmentClass.getName().hashCode() : 0;
}
@Override
public String toString() {
return "TabInfo{" +
"fragmentClass=" + fragmentClass +
'}';
}
}
The very first time you add all tabs, we need to call the method createHistory(), to create the...