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This part of development you should serialize the python RDD to the JVM. This process uses the main development of Spark to call the jar function. from pyspark.serializers import PickleSerializer, AutoBatchedSerializer rdd = sc.parallelize(range(10000)) reserialized_rdd = rdd._reserialize(Aut...

Basic Idea The notation used when describing the speed of your Python program is called Big-O notation. Let's say you have a function: def list_check(to_check, the_list): for item in the_list: if to_check == item: return True return False This is a simple function ...

Operations : Average Case (assumes parameters are randomly generated) Append : O(1) Copy : O(n) Del slice : O(n) Delete item : O(n) Insert : O(n) Get item : O(1) Set item : O(1) Iteration : O(n) Get slice : O(k) Set slice : O(n + k) Extend : O(k) Sort : O(n log n) Multiply : O(nk) x in...

A deque is a double-ended queue. class Deque: def __init__(self): self.items = [] def isEmpty(self): return self.items == [] def addFront(self, item): self.items.append(item) def addRear(self, item): self.items.insert(0,item) def removeFront(self): return self....

Operation : Average Case (assumes parameters generated randomly) : Worst case x in s : O(1) Difference s - t : O(len(s)) Intersection s&t : O(min(len(s), len(t))) : O(len(s) * len(t) Multiple intersection s1&s2&s3&...&sn : : (n-1) * O(l) where l is max(len(s1),...,len(sn)) s...

When using d3.request() or one of the convenience constructors (d3.json, d3.csv, d3.tsv, d3.html and d3.xml) there are many sources for error. There may be problems with the issued request or its response due to network errors, or the parsing might fail if the content is not well-formed. Within the...

Like page caching, action caching caches the whole page. The difference is that the request hits the Rails stack so before filters are run before the cache is served. It's extracted from Rails to actionpack-action_caching gem. A common example is caching of an action that requires authentication: ...

Decryption Code public static string Decrypt(string cipherText) { if (cipherText == null) return null; byte[] cipherBytes = Convert.FromBase64String(cipherText); using (Aes encryptor = Aes.Create()) { Rfc2898DeriveBytes pdb = ...

Let's initially understand basic types of custom validators: Inline Validator Standalone Validator Inline Validator: It is the type of the validator we create inside the class which is basically a method we define just like other methods but with extra parameters which is passed in by Yii2. ...

This is a jumbotron with a title, a content and a button. Code <div class="jumbotron"> <h1>Title text</h1> <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Donec tortor ipsum, convallis sit.</p> <p><a class="btn btn-default&...

Code <?php echo get_option( 'something_bla_bla_bla' ); ?> Output false Code <?php echo get_option( 'something_bla_bla_bla', 'Oh no!' ); ?> Output Oh no!

library(tidyr) ## example data df <- read.table(text =" numbers firstName secondName 1 1 1.5862639 0.4087477 2 2 0.1499581 0.9963923 3 3 0.4117353 0.3740009 4 4 -0.4926862 0.4437916", header = T) df # numbers firstName secondName # 1 ...

Sometimes we'd like to pause code execution to inspect the state of the application (see Debugging). When running code through the MATLAB editor, this can be done using the "Pause" button in the UI or by pressing Ctrl+c (on Windows). However, when a computation was initiated from a GUI (vi...

Including a Static Section on a page is similar to including a snippet. The only difference is instead of using the word include you use the word section. {% section 'section-file-name' %} Using this tag will "hardcode" the section into your theme at the place where you put the code an...

/* * This design have some major issues * For each new shape added the unit testing * of the GraphicEditor should be redone * When a new type of shape is added the time * for adding it will be high since the developer * who add it should understand the logic * of the Gr...

First, lets overview what we need in order to setup Hibernate correctly. @EnableTransactionManagement and @EnableJpaRepositories - we want transactional management and to use spring data repositories. DataSource - main datasource for the application. using in-memory h2 for this example. LocalCo...

In order to expose Thymeleaf templates we need to define controllers. Example: @Controller @RequestMapping("/") public class MessageController { @Autowired private MessageRepository messageRepository; @GetMapping public ModelAndView index() { It...

First, install ipset if needed. Please refer to your distribution to know how to do it. As an example, here is the command for Debian-like distributions. $ apt-get update $ apt-get install ipset Then create a configuration file to define an ipset containing the IPs for which you want to open ac...

Work in progress

Let's say we want to eliminate duplicated subsequence element from a string (it can be more than one). For example: 2,14,14,14,19 and convert it into: 2,14,19 Using gsub, we can achieve it: gsub("(\\d+)(,\\1)+","\\1", "2,14,14,14,19") [1] "2,14,19" ...