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Use threading.Thread to run a function in another thread. import threading import os def process(): print("Pid is %s, thread id is %s" % (os.getpid(), threading.current_thread().name)) threads = [threading.Thread(target=process) for _ in range(4)] for t in threads: t.sta...

As all threads are running in the same process, all threads have access to the same data. However, concurrent access to shared data should be protected with a lock to avoid synchronization issues. import threading obj = {} obj_lock = threading.Lock() def objify(key, val): print("O...

Informally, a monad is a container of elements, notated as F[_], packed with 2 functions: flatMap (to transform this container) and unit (to create this container). Common library examples include List[T], Set[T] and Option[T]. Formal definition Monad M is a parametric type M[T] with two operatio...

That would get more control over serialization, how to save and load types Implement ISerializable interface and create an empty constructor to compile [Serializable] public class Item : ISerializable { private string _name; public string Name { get { return _name; } ...

You can install NLTK over pip (pip install nltk).After it is installed, many components will not be present, and you will not be able to use some of NLTK's features. From your Python shell, run the function ntlk.download() to select which additional packages you want to install using UI. Alternati...

A deadlock is what occurs when two or more threads are waiting for eachother to complete or to release a resource in such a way that they wait forever. A typical scenario of two threads waiting on eachother to complete is when a Windows Forms GUI thread waits for a worker thread and the worker thre...

A deadlock is what occurs when two or more threads are waiting for eachother to complete or to release a resource in such a way that they wait forever. If thread1 holds a lock on resource A and is waiting for resource B to be released while thread2 holds resource B and is waiting for resource A to ...

Each group ends with a line separator. If each item in your menu has its own group you will achieve the desired graphical output. It will work only if your different groups have different android:id. Also, in menu.xml remember to mention android:checkable="true" for single item and android...

Starting a File Chooser Activity public void showFileChooser() { Intent intent = new Intent(Intent.ACTION_GET_CONTENT); // Update with mime types intent.setType("*/*"); // Update with additional mime types here using a String[]. intent.putExtra(Intent.EXTRA_M...

os.mkdir('newdir') If you need to specify permissions, you can use the optional mode argument: os.mkdir('newdir', mode=0700)

Remove the directory at path: os.rmdir(path) You should not use os.remove() to remove a directory. That function is for files and using it on directories will result in an OSError

To improve performance one might want to add indexes to columns ALTER TABLE TABLE_NAME ADD INDEX `index_name` (`column_name`) altering to add composite (multiple column) indexes ALTER TABLE TABLE_NAME ADD INDEX `index_name` (`col1`,`col2`)

Example for updating all documents where name is equal to "John": $filter = ['name' => 'John']; $document = ['name' => 'Mike']; $bulk = new \MongoDB\Driver\BulkWrite; $bulk->update( $filter, $document, ['multi' => true] ); $result = $manager->executeBu...

Example for deleting all documents where name is equal to "Peter": $bulk = new \MongoDB\Driver\BulkWrite; $filter = ['name' => 'Peter']; $bulk->delete($filter); $result = $manager->executeBulkWrite('database_name.collection_name', $bulk);

Navigation Drawers are used to navigate to top-level destinations in an app. Make sure that you have added design support library in your build.gradle file under dependencies: dependencies { // ... compile 'com.android.support:design:25.3.1' } Next, add the DrawerLayout and Navigati...

select * from sys.dm_resource_governor_workload_groups select * from sys.dm_resource_governor_resource_pools

First create a resource pool besides the default one CREATE RESOURCE POOL [PoolAdhoc] WITH(min_cpu_percent=0, max_cpu_percent=50, min_memory_percent=0, max_memory_percent=50) GO Create the worload group for the pool CREATE WORKLOAD GROUP [AdhocMedium] WITH(importa...

Sometimes specific instances of data should be used. Recreation is not desired and referencing static data would have a code smell. It is possible to specify a XmlAdapter instance the Unmarshaller should use, which allows the user to use XmlAdapters with no zero-arg constructor and/or pass data to ...

add permission in your manifest file <uses-permission android:name="android.permission.BLUETOOTH" /> In your Fragment(or Activity) Add the receiver method private BroadcastReceiver mBluetoothStatusChangedReceiver = new BroadcastReceiver() { @Override public void o...

Headings can be used to describe the topic they precede and they are defined with the <h1> to <h6> tags. Headings support all the global attributes. <h1> defines the most important heading. <h6> defines the least important heading. Defining a heading: <h1>Headin...