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Articles on Trending Technologies
Technical articles with clear explanations and examples
Finding the simple non-isomorphic graphs with n vertices in a graph
Two graphs are isomorphic if one can be transformed into the other by renaming its vertices. In other words, they have the same structure even if the vertices are labeled differently. Non-isomorphic graphs are graphs that have genuinely different structures − no renaming of vertices can make one look like the other. When counting simple non-isomorphic graphs with n vertices, we look for all structurally distinct graphs possible, ignoring vertex labels. Problem Statement How many simple non-isomorphic graphs are possible with 3 vertices? Solution With 3 vertices, there are at most ⌈3C2⌉ = 3 possible ...
Read MoreComposition of Functions of Set
Two functions f: A → B and g: B → C can be composed to give a composition g o f. This is a function from A to C defined by − (g o f)(x) = g(f(x)) In composition, the output of the first function becomes the input of the second function. The function on the right (f) is applied first, and then the function on the left (g) is applied to the result. A B C ...
Read MoreIntroduction to Mathematical Logic
The rules of mathematical logic specify methods of reasoning mathematical statements. Greek philosopher, Aristotle, was the pioneer of logical reasoning. Logical reasoning provides the theoretical base for many areas of mathematics and consequently computer science. It has many practical applications in computer science like design of computing machines, artificial intelligence, definition of data structures for programming languages etc.Major CategoriesMathematical logics can be broadly categorized into three categories.Propositional Logic − Propositional Logic is concerned with statements to which the truth values, "true" and "false", can be assigned. The purpose is to analyse these statements either individually or in a composite manner.Predicate ...
Read MoreData Replication from SAP PO to SQL Server
It is important to note that SAP PO (Process Orchestration) is not a data source but a middleware − it does not store or contain business data itself. To replicate data to SQL Server, you extract data from the actual source system (such as SAP ERP) through SAP PO, and load it into SQL Server using a JDBC adapter. What Is SAP PI/PO? SAP Process Integration (PI), also known as SAP Process Orchestration (PO), enables cross-system communication and integration. It allows you to connect SAP and non-SAP systems based on different technologies like Java and SAP ABAP. It ...
Read MoreHow to call a function with argument list in Python?
The purpose of a function is to perform a specific task using code blocks. Functions save time by eliminating unnecessary copying and pasting of code. If you need to make a change, you only update the function in one place rather than searching through your entire program. This follows the DRY (Don't Repeat Yourself) principle in software development. Defining a Function in Python Python functions are created using the following syntax − def function_name(parameters): function body A function is defined using the def keyword followed by the function name and ...
Read MoreHow to expand tabs in string to multiple spaces in Python?
In Python, handling white spaces between strings is easy. Sometimes, we may want to add space in a string, but we are not sure exactly how much. Python provides different ways to manage this, and one useful method is the expandtabs() method. Using the expandtabs() Method The expandtabs() method in Python is used to replace tab characters (\t) in a string with spaces. It returns a new string where each \t is replaced with the number of spaces needed to reach the next tab stop. You can control how many spaces are used by passing a tabsize value ...
Read MoreCount the number of items in an array in MongoDB?
To count the number of items in an array in MongoDB, you can use the $size operator within the $project stage of an aggregation pipeline. The $size operator returns the number of elements in a specified array field. The syntax is − db.yourCollectionName.aggregate({ $project: { anyFieldName: { $size: "$yourArrayName" } } }).pretty(); Creating a Sample Collection To understand the above syntax, let us create a collection with documents. Each document contains a StudentMarks array with a different number of elements ? ...
Read MoreHow to select a single field in MongoDB?
You can select a single field in MongoDB using the projection parameter in the find() method. Projection lets you specify which fields to include or exclude in the query results. The syntax is − db.yourCollectionName.find( {"yourFieldName": yourValue}, {"yourSingleFieldName": 1, _id: 0} ); In the above syntax, "yourSingleFieldName": 1 means include this field in the result, and _id: 0 means exclude the _id field which MongoDB includes by default. Creating a Sample Collection To understand the above syntax, let us create a collection with documents ? db.singleFieldDemo.insertOne({"StudentName": "David", "StudentAge": 28}); ...
Read More"Structured" grouping query in MongoDB to display result with a new field displaying the count
For this, use $group in MongoDB with aggregate(). The $group stage groups input documents by the specified _id expression and for each distinct grouping, outputs a document. Structured grouping allows you to create complex grouping hierarchies and add calculated fields like counts to your results. Let us first create a collection with documents − > db.demo534.insertOne({_id:10, "ProductId":100, "ProductName":"Product-1"}); { "acknowledged" : true, "insertedId" : 10 } > db.demo534.insertOne({_id:11, "ProductId":100, "ProductName":"Product-2"}); { "acknowledged" : true, "insertedId" : 11 } > db.demo534.insertOne({_id:12, "ProductId":101, "ProductName":"Product-1"}); { "acknowledged" : true, "insertedId" : 12 } Display all documents from a ...
Read More"Toggle" query in MongoDB?
To implement a toggle query in MongoDB, you need to find the document first and then use the update operation to toggle the boolean field value. The toggle operation switches a boolean value from true to false or vice versa. Let us first create a collection with sample documents − > db.toggleDemo.insertOne({"CustomerName":"John Smith", "CustomerAge":28, "isMarried":true}); { "acknowledged" : true, "insertedId" : ObjectId("5cc7be138f9e6ff3eb0ce43b") } > db.toggleDemo.insertOne({"CustomerName":"David Miller", "CustomerAge":25, "isMarried":false}); { "acknowledged" : true, "insertedId" : ObjectId("5cc7be2e8f9e6ff3eb0ce43c") } Following is the query to display all ...
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