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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...

Code running in different processes do not, by default, share the same data. However, the multiprocessing module contains primitives to help share values across multiple processes. import multiprocessing plain_num = 0 shared_num = multiprocessing.Value('d', 0) lock = multiprocessing.Lock() ...

SQL Server 2012 Returns a string that is the result of two or more strings joined together. CONCAT accepts two or more arguments. SELECT CONCAT('This', ' is', ' my', ' string') -- returns 'This is my string' Note: Unlike concatenating strings using the string concatenation operator (+), when ...

By default, plot() creates a new figure each time it is called. It is possible to plot on an existing axis by passing the ax parameter. plt.figure() # create a new figure ax = plt.subplot(121) # create the left-side subplot df1.plot(ax=ax) # plot df1 on that subplot ax = plt.subplot(122) # c...

In this example, a model will learn to classify fruits given certain features, using the Labels for training. WeightColorLabel0.5greenapple0.6purpleplum3greenwatermelon0.1redcherry0.5redapple Here the a model will take Weight and Color as features to predict the Label. For instance [0.15, 'red'] s...

We can use flatten() in order to lazily reduce the nesting of a multi-dimensional sequence. For example, lazy flattening a 2D array into a 1D array: // A 2D array of type [[Int]] let array2D = [[1, 3], [4], [6, 8, 10], [11]] // A FlattenBidirectionalCollection<[[Int]]> let lazilyFlatten...

Melting: The basics Melting is used to transform data from wide to long format. Starting with a wide data set: DT = data.table(ID = letters[1:3], Age = 20:22, OB_A = 1:3, OB_B = 4:6, OB_C = 7:9) We can melt our data using the melt function in data.table. This returns another data.table in long...

To create a libary , you should use File -> New -> New Module -> Android Library. This will create a basic library project. When that's done, you must have a project that is set up the following manner: [project root directory] [library root directory] [gradle] build.gradle...

Perform the following steps to create the library: Create a GitHub account. Create a Git repository containing your library project. Modify your library project's build.gradle file by adding the following code: apply plugin: 'com.github.dcendents.android-maven' ... // Build a j...

The PHP execution operator consists of backticks (``) and is used to run shell commands. The output of the command will be returned, and may, therefore, be stored in a variable. // List files $output = `ls`; echo "<pre>$output</pre>"; Note that the execute operator and sh...

PubNub Access Manager (PAM) extends PubNub's existing security framework by allowing developers to create and enforce secure access to channels throughout the PubNub Real Time Network. Access Manager allows you to manage granular permissions for your realtime apps and data streams, create multiple ...

Validate that an attribute's value matches a regular expression using format and the with option. class User < ApplicationRecord validates :name, format: { with: /\A\w{6,10}\z/ } end You can also define a constant and set its value to a regular expression and pass it to the with: option. ...

You can check if a value is included in an array using the inclusion: helper. The :in option and its alias, :within show the set of acceptable values. class Country < ApplicationRecord validates :continent, inclusion: { in: %w(Africa Antartica Asia Australia ...

If you use the [NonSerialized] attribute, then that member will always have its default value after deserialization (ex. 0 for an int, null for string, false for a bool, etc.), regardless of any initialization done in the object itself (constructors, declarations, etc.). To compensate, the attribut...

Implements a serialization surrogate selector that allows one object to perform serialization and deserialization of another As well allows to properly serialize or deserialize a class that is not itself serializable Implement ISerializationSurrogate interface public class ItemSurrogate : ISerial...

In order to dynamically decide what beans to inject, we can use FactoryBeans. These are classes which implement the factory method pattern, providing instances of beans for the container. They are recognized by Spring and can be used transparently, without need to know that the bean comes from a fac...

This is a nice trick to add a link to code, so it will be easy to jump to the code that issued the log. With the following code, this call: MyLogger.logWithLink("MyTag","param="+param); Will result in: 07-26...012/com.myapp D/MyTag: MyFrag:onStart(param=3) (MyFrag.java:236...

This is the basic way to insert data from another table with the SELECT statement. INSERT INTO `tableA` (`field_one`, `field_two`) SELECT `tableB`.`field_one`, `tableB`.`field_two` FROM `tableB` WHERE `tableB`.clmn <> 'someValue' ORDER BY `tableB`.`sorting_clmn`; You can...

Reflection is useful but fragile. Consider this: let mi = typeof<System.String>.GetMethod "StartsWith" The problems with this kind of code are: The code doesn't work because there are several overloads of String.StartsWith Even if there wouldn't be any overloads right now la...

Detailed instructions on getting docusignapi set up or installed.