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Shiny can run as a standalone application on your local computer, on a server that can provide shiny apps to multiple users (using shiny server), or on shinyapps.io. Installing Shiny on a local computer: in R/RStudio, run install.packages("shiny") if installing from CRAN, or devtools::i...
// Converts the string representation of a date and time to its DateTime equivalent var dateTime = DateTime.Parse("14:23 22 Jul 2016"); Console.WriteLine(dateTime.ToString());
// Converts the specified string representation of a date and time to its DateTime equivalent and returns a value that indicates whether the conversion succeeded string[] dateTimeStrings = new []{ "14:23 22 Jul 2016", "99:23 2x Jul 2016", "22/7/2016 14:23:0...
Data from a POST request is stored in the superglobal $_POST in the form of an associative array. Note that accessing a non-existent array item generates a notice, so existence should always be checked with the isset() or empty() functions, or the null coalesce operator. Example: $from = isset($_...
Data from a GET request is stored in the superglobal $_GET in the form of an associative array. Note that accessing a non-existent array item generates a notice, so existence should always be checked with the isset() or empty() functions, or the null coalesce operator. Example: (for URL /topics.ph...
Quickstart for Jekyll $ gem install jekyll $ jekyll new my-awesome-site $ cd my-awesome-site ~/my-awesome-site $ jekyll serve Now browse to http://localhost:4000 Quickstart for Jekyll with Bundler $ gem install jekyll bundler $ jekyll new my-awesome-site $ cd my-awesome-site ~/my...
First, we'll need to do some setup to get HStoreField working. make sure django.contrib.postgres is in your `INSTALLED_APPS Add HStoreExtension to your migrations. Remember to put HStoreExtension before any CreateModel or AddField migrations. from django.contrib.postgres.operations import HSt...
-> Note: make sure you set up HStoreField first before going on with this example. (above) No parameters are required for initializing a HStoreField. from django.contrib.postgres.fields import HStoreField from django.db import models class Catalog(models.model): name = models.C...
Pass a native python dictionary mapping strings to strings to create(). Catalog.objects.create(name='Library of Congress', titles_to_authors={ 'Using HStoreField with Django': 'CrazyPython and la communidad', 'Flabbergeists and thingamajigs': 'La Artista Fooista', 'Pro Git': 'Scott C...
Catalog.objects.filter(titles__Pro_Git='Scott Chacon and Ben Straub')
Pass a dict object to field_name__contains as a keyword argument. Catalog.objects.filter(titles__contains={ 'Pro Git': 'Scott Chacon and Ben Straub'}) Equivalent to the SQL operator `@>`.
You often find yourself in a situation where you need to find a variables corresponding value, and collections got you covered. In the example below we got three different locales in an array with a corresponding calling code assigned. We want to be able to provide a locale and in return get the as...
# Fetch and install package to setup access to the official APT repository wget https://packages.erlang-solutions.com/erlang-solutions_1.0_all.deb sudo dpkg -i erlang-solutions_1.0_all.deb # Update package index sudo apt-get update # Install Erlang and Elixir sudo apt-get install esl-erlan...
5 With ES5+, the Object.create function can be used to create an Object with any other Object as it's prototype. const anyObj = { hello() { console.log(`this.foo is ${this.foo}`); }, }; let objWithProto = Object.create(anyObj); objWithProto.foo = 'bar'; objWithProto.hell...
Run command below to install nginx. sudo apt-get install nginx By default, Nginx automatically starts when it is installed. You can access the default Nginx landing page to confirm that the software is running properly by visiting your server's domain name or public IP address in your web browse...
Dim array2D(,) As Integer = {{1, 2, 3}, {4, 5, 6}} ' array2D(0, 0) is 1 ; array2D(0, 1) is 2 ; array2D(1, 0) is 4 Dim array3D(,,) As Integer = {{{1, 2, 3}, {4, 5, 6}}, {{7, 8, 9}, {10, 11, 12}}} ' array3D(0, 0, 0) is 1 ; array3D(0, 0, 1) is 2 ' array3D(0, 1, 0) is 4 ; array3D(1, 0, 0) is 7 ...
Note the parenthesis to distinguish between a jagged array and a multidimensional array SubArrays can be of different length Dim jaggedArray()() As Integer = { ({1, 2, 3}), ({4, 5, 6}), ({7}) } ' jaggedArray(0) is {1, 2, 3} and so jaggedArray(0)(0) is 1 ' jaggedArray(1) is {4, 5, 6} and so jagge...
valgrind ./my-program arg1 arg2 < test-input This will run your program and produce a report of any allocations and de-allocations it did. It will also warn you about common errors like using uninitialized memory, dereferencing pointers to strange places, writing off the end of blocks allocate...
You can also turn on more tests, such as: valgrind -q --tool=memcheck --leak-check=yes ./my-program arg1 arg2 < test-input See valgrind --help for more information about the (many) options, or look at the documentation at http://valgrind.org/ for detailed information about what the output mea...
Here is a program that calls malloc but not free: #include <stdio.h> #include <stdlib.h> int main(int argc, char **argv) { char *s; s = malloc(26); // the culprint return 0; } With no extra arguments, valgrind will not look for this error. But if we turn on...

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