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You can use $group operator with _id: null. Following is the syntax −db.yourCollectionName.aggregate([{$group: {_id:null, "anyFieldName": {$avg:"$yourFieldName"} } }]);Let us first create a collection with documents −> db.caculateTheAverageValueDemo.insertOne({"Population":100}); { "acknowledged" : true, "insertedId" : ObjectId("5cd68a197924bb85b3f4895f") } > db.caculateTheAverageValueDemo.insertOne({"Population":500}); { "acknowledged" : true, "insertedId" : ObjectId("5cd68a1c7924bb85b3f48960") } > db.caculateTheAverageValueDemo.insertOne({"Population":200}); { "acknowledged" : true, "insertedId" : ObjectId("5cd68a237924bb85b3f48961") } > db.caculateTheAverageValueDemo.insertOne({"Population":100}); { "acknowledged" : true, "insertedId" : ObjectId("5cd68a297924bb85b3f48962") } > db.caculateTheAverageValueDemo.insertOne({"Population":100}); { "acknowledged" : true, "insertedId" : ObjectId("5cd68a2e7924bb85b3f48963") }Following is the query to display all documents from a collection with the help of find() ... Read More
In Java you can declare three types of variables namely, instance variables, static variables and, local variables.Local variables − Variables defined inside methods, constructors or blocks are called local variables. The variable will be declared and initialized within the method and the variable will be destroyed when the method has completed.Instance variables − Instance variables are variables within a class but outside any method. These variables are initialized when the class is instantiated. Instance variables can be accessed from inside any method, constructor or blocks of that particular class.Class (static) variables − Class variables are variables declared within a class, ... Read More
The HTML DOM Input Email size property returns/sets the size property for input Email. If not defined, this property returns ‘20’.SyntaxFollowing is the syntax −Returning size attributeinputEmailObject.sizeSet size property to a numberinputEmailObject.size = numberExampleLet us see an example of Input Email size property − Live Demo Input Email size form { width:70%; margin: 0 auto; text-align: center; } * { padding: 2px; margin:5px; } input[type="button"] { border-radius: 10px; } ... Read More
In this section we will see how to print a number 100 times in C. There are some constraints. We cannot use loops, recursions or macro expansions.To solve this problem we will use the setjump and longjump in C. The setjump() and longjump() is located at setjmp.h library. The syntax of these two functions are like below.Example#include #include jmp_buf buf; main() { int x = 1; setjmp(buf); //set the jump position using buf printf("5"); // Prints a number x++; if (x
Yes, we can get the supported image types with ImageIO class in Java. The following is an example to get supported image types in Java:Examplepackage my; import javax.imageio.ImageIO; public class SwingDemo { public static void main(String[] args) throws Exception { String[] imgTypes = ImageIO.getReaderFileSuffixes(); System.out.print("Supported Image Types = "); for (String type : imgTypes) { System.out.print("" + type); } } }OutputSupported Image Types = jpg tif tiff bmp gif png wbmp jpeg
This example demonstrate about Custom Notification Sounds for Android Oreo and BeyondStep 1 − Create a new project in Android Studio, go to File ⇒ New Project and fill all required details to create a new project.Step 2 − Add the following code to res/layout/activity_main.xml. Step 3 − Add a sound into raw folderStep 4 − Add the following code to src/MainActivity.javapackage app.tutorialspoint.com.notifyme ; import android.app.NotificationChannel ; import android.app.NotificationManager ; import android.content.ContentResolver ; import android.content.Context ; import android.graphics.Color ; import android.media.AudioAttributes ; import android.net.Uri ; import android.support.v4.app.NotificationCompat ; import android.support.v7.app.AppCompatActivity ; import android.os.Bundle ; import android.view.View ; ... Read More
You can use only $pull operator that removes and updates the existing record in MongoDB. Let us first create a collection with documents −> db.removeDemo.insertOne( ... { ... "UserName" : "Larry", ... "UserDetails" : [ ... { ... "_id" : 101, ... "UserEmailId" : "976Larry@gmail.com", ... } ... ] ... } ... ); { "acknowledged" : true, "insertedId" : ObjectId("5cc7f9f88f9e6ff3eb0ce446") } > db.removeDemo.insertOne( ... { ... ... Read More
To get the count of siblings of this node, use the getSiblingCount() method. Let’s say you have a node with 4 child nodes. Find the sibling of any of this node’s child node. Here, “eight” is the child node −eight.getSiblingCount());Note − Remember, a node is it’s own sibling.The following is an example to get the number of siblings of this node in a JTree −Examplepackage my; import javax.swing.JFrame; import javax.swing.JTree; import javax.swing.tree.DefaultMutableTreeNode; public class SwingDemo { public static void main(String[] args) throws Exception { JFrame frame = new JFrame("Demo"); DefaultMutableTreeNode node = new DefaultMutableTreeNode("Products"); DefaultMutableTreeNode node1 = new DefaultMutableTreeNode("Clothing (Product1 - P66778)"); DefaultMutableTreeNode node2 = new DefaultMutableTreeNode("Accessories (Product2 - P66779)"); DefaultMutableTreeNode node3 = new DefaultMutableTreeNode("Home Decor (Product3 - ... Read More
Let’s say you have saved the Login date of users. Now, you want the users who logged in between specific dates i.e. login date. For this, use $gte and $lt operator along with count(). Let us first create a collection with documents −> db.findDataByDateDemo.insertOne({"UserName":"John", "UserLoginDate":new ISODate("2019-01-31")}); { "acknowledged" : true, "insertedId" : ObjectId("5cdd8cd7bf3115999ed511ed") } > db.findDataByDateDemo.insertOne({"UserName":"Larry", "UserLoginDate":new ISODate("2019-02-01")}); { "acknowledged" : true, "insertedId" : ObjectId("5cdd8ce7bf3115999ed511ee") } > db.findDataByDateDemo.insertOne({"UserName":"Sam", "UserLoginDate":new ISODate("2019-05-02")}); { "acknowledged" : true, "insertedId" : ObjectId("5cdd8cf3bf3115999ed511ef") } > db.findDataByDateDemo.insertOne({"UserName":"David", "UserLoginDate":new ISODate("2019-05-16")}); { "acknowledged" : true, "insertedId" : ObjectId("5cdd8d00bf3115999ed511f0") } > db.findDataByDateDemo.insertOne({"UserName":"Carol", ... Read More
This is a C++ program in which we generate a undirected random graph for the given edges ‘e’. This algorithm basically implements on a big network and time complexity of this algorithm is O(log(n)).AlgorithmBegin Function GenerateRandomGraphs(), has ‘e’ as the number edges in the argument list. Initialize i = 0 while(i < e) edge[i][0] = rand()%N+1 edge[i][1] = rand()%N+1 Increment I; For i = 0 to N-1 Initialize count = 0 For j = 0 to e-1 ... Read More