Tutorial by Examples: is

Unlike Java, Dart doesn’t have the keywords public, protected, and private. If an identifier starts with an underscore _, it’s private to its library. If you for example have class A in a separate library file (eg, other.dart), such as: library other; class A { int _private = 0; testA()...

If you want PHP to display runtime errors on the page, you have to enable display_errors, either in the php.ini or using the ini_set function. You can choose which errors to display, with the error_reporting (or in the ini) function, which accepts E_* constants, combined using bitwise operators. P...

You can define a private rules to disable read and write access to your database by users. With these rules, you can only access the database when you have administrative privileges (which you can get by accessing the database through the Firebase console or by signing in from a server). // These...

If you have one of the supported Linux distributions, you can follow the steps on the .NET Core website: https://www.microsoft.com/net If you have an unsupported distribution: Download the .NET Core SDK from the links, picking the distribution closer to the used one. https://www.microsoft.com/net...

# application.rb config.time_zone = 'Eastern Time (US & Canada)' config.active_record.default_timezone = :local

N-bit deep shift register with asynchronous reset. module shift_register #( parameter REG_DEPTH = 16 )( input clk, //clock signal input ena, //enable signal input rst, //reset signal input data_in, //input bit output data_out //output bit ); reg [REG_DE...

If you are optimizing all images manually, disable APT Cruncher for a smaller APK file size. android { aaptOptions { cruncherEnabled = false } }

/* within a class, def, trait or object, but not a constructor */ synchronized { /* code to run when an intrisctic lock on `this` is acquired */ /* no other thread can get the this lock unless execution is suspended with * `wait` on `this` */ }

Start with importing the library. from amqpstorm import Connection from amqpstorm import Message Next we need to open a connection to the RabbitMQ server. connection = Connection('127.0.0.1', 'guest', 'guest') After that we need to set up a channel. Each connection can have multiple channel...

Some teams find that they want to leave console log statements in their code, but not have them display in production. They will override the logging functions if a variable isn't set (possibly an environment variable). Additionally, this may qualify as a security feature in some situations. if (...

SELECT DISTINCT ContinentCode FROM Countries; This query will return all DISTINCT (unique, different) values from ContinentCode column from Countries table ContinentCodeOCEUASNAAF SQLFiddle Demo

If you want to remove duplicates from a result, you can use .distinct(): Customers.select(:country).distinct This queries the database as follows: SELECT DISTINCT "customers"."country" FROM "customers" .uniq() has the same effect. With Rails 5.0 it got deprecate...

anyNA reports whether any missing values are present; while is.na reports missing values elementwise: vec <- c(1, 2, 3, NA, 5) anyNA(vec) # [1] TRUE is.na(vec) # [1] FALSE FALSE FALSE TRUE FALSE ìs.na returns a logical vector that is coerced to integer values under arithmetic operation...

There are currently three YouTube APIs available to the public: YouTube Data API YouTube Analytics API YouTube Reporting API Each of these offer different functionality and are treated as separate, individual APIs. Since YouTube is a subsidiary of Google, the various YouTube APIs are provid...

Above I noticed an example to remove items from a List within a Loop and I thought of another example that may come in handy this time using the Iterator interface. This is a demonstration of a trick that might come in handy when dealing with duplicate items in lists that you want to get rid of. N...

Starting with a three-dimensional list: alist = [[[1,2],[3,4]], [[5,6,7],[8,9,10], [12, 13, 14]]] Accessing items in the list: print(alist[0][0][1]) #2 #Accesses second element in the first list in the first list print(alist[1][1][2]) #10 #Accesses the third element in the second list in...

Introduction and motivation Expression templates (denoted as ETs in the following) are a powerful template meta-programming technique, used to speed-up calculations of sometimes quite expensive expressions. It is widely used in different domains, for example in implementation of linear algebra ...

Lets suppose you have 2 Lists A and B, and you want to remove from B all the elements that you have in A the method in this case is List.removeAll(Collection c); #Example: public static void main(String[] args) { List<Integer> numbersA = new ArrayList<>(); List<Intege...

Python 2 includes a cmp function which allows you to determine if one object is less than, equal to, or greater than another object. This function can be used to pick a choice out of a list based on one of those three options. Suppose you need to print 'greater than' if x > y, 'less than' if x &...

If you need to apply a setting dynamically after the cluster has already started, and it can actually be set dynamically, then you can set it using _cluster/settings API. Persistent settings are one of the two type of cluster-wide settings that can be applied. A persistent setting will survive a fu...