Tutorial by Examples: le

Creating an empty table is as simple as this: local empty_table = {} You can also create a table in the form of a simple array: local numeric_table = { "Eve", "Jim", "Peter" } -- numeric_table[1] is automatically "Eve", numeric_table[2] is "Ji...

Normally, a Docker container persists after it has exited. This allows you to run the container again, inspect its filesystem, and so on. However, sometimes you want to run a container and delete it immediately after it exits. For example to execute a command or show a file from the filesystem. Dock...

In this example we will write a basic program that checks the number of inputs and outputs passed to a MEX-function. As a starting point, we need to create a C++ file implementing the "MEX gateway". This is the function executed when the file is called from MATLAB. testinputs.cpp // Mat...

An std::map takes (key, value) pairs as input. Consider the following example of std::map initialization: std::map < std::string, int > ranking { std::make_pair("stackoverflow", 2), std::make_pair("docs-beta", 1) }; In an std::...

Removing all elements: std::multimap< int , int > mmp{ {1, 2}, {3, 4}, {6, 5}, {8, 9}, {3, 4}, {6, 7} }; mmp.clear(); //empty multimap Removing element from somewhere with the help of iterator: std::multimap< int , int > mmp{ {1, 2}, {3, 4}, {6, 5}, {8, 9}, {3, 4}, {6, 7} }; ...

An element can be inserted into a std::map only if its key is not already present in the map. Given for example: std::map< std::string, size_t > fruits_count; A key-value pair is inserted into a std::map through the insert() member function. It requires a pair as an argument: fruits_c...

The container std::map has a member function empty(), which returns true or false, depending on whether the map is empty or not. The member function size() returns the number of element stored in a std::map container: std::map<std::string , int> rank {{"facebook.com", 1} ,{"goo...

SELECT DisplayName, JoinDate, Reputation FROM Users ORDER BY JoinDate, Reputation DisplayNameJoinDateReputationCommunity2008-09-151Jeff Atwood2008-09-1625784Joel Spolsky2008-09-1637628Jarrod Dixon2008-10-0311739Geoff Dalgas2008-10-0312567

INSERT INTO Customers (FName, LName, PhoneNumber) SELECT FName, LName, PhoneNumber FROM Employees This example will insert all Employees into the Customers table. Since the two tables have different fields and you don't want to move all the fields over, you need to set which fields to insert int...

Each individual CSS Selector has its own specificity value. Every selector in a sequence increases the sequence's overall specificity. Selectors fall into one of three different specificity groups: A, B and c. When multiple selector sequences select a given element, the browser uses the styles appli...

The Lua standard library provides a pairs function which iterates over the keys and values of a table. When iterating with pairs there is no specified order for traversal, even if the keys of the table are numeric. for key, value in pairs(input_table) do print(key, " -- ", value) en...

Reflection is often used as part of software testing, such as for the runtime creation/instantiation of mock objects. It's also great for inspecting the state of an object at any given point in time. Here's an example of using Reflection in a unit test to verify a protected class member contains the...

The first two arguments to format are an output stream and a control string. Basic use does not require additional arguments. Passing t as the stream writes to *standard-output*. > (format t "Basic Message") Basic Message nil That expression will write Basic Message to standard ou...

Like in several other parts of the I/O library, functions that implicitly use a standard stream have a counterpart in System.IO that performs the same job, but with an extra parameter at the left, of type Handle, that represents the stream being handled. For instance, getLine :: IO String has a cou...

A bit counter-intuitive to the way most other languages' standard I/O libraries do it, Haskell's isEOF does not require you to perform a read operation before checking for an EOF condition; the runtime will do it for you. import System.IO( isEOF ) eofTest :: Int -> IO () eofTest line = do ...

SQL TermsMongoDB TermsDatabaseDatabaseTableCollectionEntity / RowDocumentColumnKey / FieldTable JoinEmbedded DocumentsPrimary KeyPrimary Key (Default key _id provided by mongodb itself)

This uses the Dropbox .NET SDK to download a file from the Dropbox API at the remote path to the local file "Test", while tracking progress: var response = await client.Files.DownloadAsync(path); ulong fileSize = response.Response.Size; const int bufferSize = 1024 * 1024; var buffer ...

5 We can avoid a property from showing up in for (... in ...) loops The enumerable property of the property descriptor tells whether that property will be enumerated while looping through the object's properties. var obj = { }; Object.defineProperty(obj, "foo", { value: 'show', enu...

Syntax: SELECT * FROM table_name Using the asterisk operator * serves as a shortcut for selecting all the columns in the table. All rows will also be selected because this SELECT statement does not have a WHERE clause, to specify any filtering criteria. This would also work the same way if you...

This query will return the number of tables in the specified database. USE YourDatabaseName SELECT COUNT(*) from INFORMATION_SCHEMA.TABLES WHERE TABLE_TYPE = 'BASE TABLE' Following is another way this can be done for all user tables with SQL Server 2008+. The reference is here. SELECT COUNT(...