Tutorial by Examples: s

To create a parallel collection from a sequential collection, call the par method. To create a sequential collection from a parallel collection, call the seq method. This example shows how you turn a regular Vector into a ParVector, and then back again: scala> val vect = (1 to 5).toVector vect:...

Do not use parallel collections when the collection elements must be received in a specific order. Parallel collections perform operations concurrently. That means that all of the work is divided into parts and distributed to different processors. Each processor is unaware of the work being done by...

The most common mode of using TensorFlow involves first building a dataflow graph of TensorFlow operators (like tf.constant() and tf.matmul(), then running steps by calling the tf.Session.run() method in a loop (e.g. a training loop). A common source of memory leaks is where the training loop conta...

To improve memory allocation performance, many TensorFlow users often use tcmalloc instead of the default malloc() implementation, as tcmalloc suffers less from fragmentation when allocating and deallocating large objects (such as many tensors). Some memory-intensive TensorFlow programs have been kn...

PyPar is a library that uses the message passing interface (MPI) to provide parallelism in Python. A simple example in PyPar (as seen at https://github.com/daleroberts/pypar) looks like this: import pypar as pp ncpus = pp.size() rank = pp.rank() node = pp.get_processor_name() print 'I am r...

Detailed instructions on getting dropwizard set up or installed.

There are several scopes that are available only in a web-aware application context: request - new bean instance is created per HTTP request session - new bean instance is created per HTTP session application - new bean instance is created per ServletContext globalSession - new bean instance i...

When using async queries, you can execute multiple queries at the same time, but not on the same context. If the execution time of one query is 10s, the time for the bad example will be 20s, while the time for the good example will be 10s. Bad Example IEnumerable<TResult1> result1; IEnumera...

All lines must be terminated with a line feed character (LF, ASCII value 10) and not for instance CR or CR+LF. There may be no trailing white space at the end of a line. The name of a source file must equal the name of the class it contains followed by the .java extension, even for fil...

Apart from LF the only allowed white space character is Space (ASCII value 32). Note that this implies that other white space characters (in, for instance, string and character literals) must be written in escaped form. \', \", \\, \t, \b, \r, \f, and \n should be preferred over corres...

// First java/javax packages import java.util.ArrayList; import javax.tools.JavaCompiler; // Then third party libraries import com.fasterxml.jackson.annotation.JsonProperty; // Then project imports import com.example.my.package.ClassA; import com.example.my.package.ClassB; // Then stat...

Order of class members Class members should be ordered as follows: Fields (in order of public, protected and private) Constructors Factory methods Other Methods (in order of public, protected and private) Ordering fields and methods primarily by their access modifiers or identifier is not ...

class ExampleClass { // Access modifiers first (don't do for instance "static public") public static void main(String[] args) { System.out.println("Hello World"); } } interface ExampleInterface { // Avoid 'public' and 'abstract' since they are imp...

Source code and comments should generally not exceed 80 characters per line and rarely if ever exceed 100 characters per line, including indentation. The character limit must be judged on a case by case basis. What really matters is the semantical “density” and readability of the line. Making l...

int someMethod(String aString, List<Integer> aList, Map<String, String> aMap, int anInt, long aLong, Set<Number> aSet, double aDouble) { … } int someMethod(String aString, List&...

If a line approaches the maximum character limit, always consider breaking it down into multiple statements / expressions instead of wrapping the line. Break before operators. Break before the . in chained method calls. popupMsg("Inbox notification: You have " + newMsgs + &...

Vertical Whitespace A single blank line should be used to separate… Package declaration Class declarations Constructors Methods Static initializers Instance initializers …and may be used to separate logical groups of import statements fields statements Multiple consec...

One variable per declaration (and at most one declaration per line) Square brackets of arrays should be at the type (String[] args) and not on the variable (String args[]). Declare a local variable right before it is first used, and initialize it as close to the declaration as possible.

Declaration annotations should be put on a separate line from the declaration being annotated. @SuppressWarnings("unchecked") public T[] toArray(T[] typeHolder) { ... } However, few or short annotations annotating a single-line method may be put on the same line as the method if...

Runnable r = () -> System.out.println("Hello World"); Supplier<String> c = () -> "Hello World"; // Collection::contains is a simple unary method and its behavior is // clear from the context. A method reference is preferred here. appendFilter(goodStrings::cont...