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<plugin> <groupId>org.apache.tomcat.maven</groupId> <artifactId>tomcat7-maven-plugin</artifactId> <version>2.1</version> <executions> <execution> <...

To be able to debug an application is very important to understand the flow of an application's logic and data. It helps solving logical bugs and adds value to the programming experience and code quality. Two popular gems for debugging are debugger (for ruby 1.9.2 and 1.9.3) and byebug (for ruby &g...

com.google.gson library needs to be added to use this code. Here is the example string: String companyDetails = {"companyName":"abcd","address":"abcdefg"} JSON strings can be parsed using below syntax in Java: JsonParser parser = new JsonParser(); Json...

The word count program is like the "Hello World" program in MapReduce. Hadoop MapReduce is a software framework for easily writing applications which process vast amounts of data (multi-terabyte data-sets) in-parallel on large clusters (thousands of nodes) of commodity hardware in a relia...

PM2 lets you run your nodejs scripts forever. In the event that your application crashes, PM2 will also restart it for you. Install PM2 globally to manager your nodejs instances npm install pm2 -g Navigate to the directory in which your nodejs script resides and run the following command each t...

To start the process: $ forever start index.js warn: --minUptime not set. Defaulting to: 1000ms warn: --spinSleepTime not set. Your script will exit if it does not stay up for at least 1000ms info: Forever processing file: index.js List running Forever instances: $ forever list i...

In Python 2, True, False and None are built-in constants. Which means it's possible to reassign them. Python 2.x2.0 True, False = False, True True # False False # True You can't do this with None since Python 2.4. Python 2.x2.4 None = None # SyntaxError: cannot assign to None In ...

When adding a LIMIT to a UNION, this is the pattern to use: ( SELECT ... ORDER BY x LIMIT 10 ) UNION ( SELECT ... ORDER BY x LIMIT 10 ) ORDER BY x LIMIT 10 Since you cannot predict which SELECT(s) will the "10" will come from, you need to get 10 from each, then further whittle do...

Strict mode also prevents you from deleting undeletable properties. "use strict"; delete Object.prototype; // throws a TypeError The above statement would simply be ignored if you don't use strict mode, however now you know why it does not execute as expected. It also prevents you fr...

std::vector<std::string> split(const std::string &str, std::string regex) { std::regex r{ regex }; std::sregex_token_iterator start{ str.begin(), str.end(), r, -1 }, end; return std::vector<std::string>(start, end); } split("Some string\t with whitespace &...

Remember to npm install all the files into devDependencies first. E.g. npm install --save-dev gulp gulp-concat gulp-rename gulp-uglify gulp-uglifycss Gulpfile.js var gulp = require('gulp'); var gulp_concat = require('gulp-concat'); var gulp_rename = require('gulp-rename'); var gulp_uglify = ...

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:...

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...

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...

In [188]: s = pd.Series(["a","b","c","a","c"], dtype="category") In [189]: s Out[189]: 0 a 1 b 2 c 3 a 4 c dtype: category Categories (3, object): [a, b, c] In [190]: df = pd.DataFrame({"A":["a&q...

package com.example.my.package; The package declaration should not be line wrapped, regardless of whether it exceeds the recommended maximum length of a line.

// 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...