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Logistic Regression is a statistical technique to predict the binary outcome. It’s not a new thing as it is currently being applied in areas ranging from finance to medicine to criminology and other social sciences.In this section we are going to develop logistic regression using python, though you can implement same using other languages like R.InstallationWe’re going to use below libraries in our example program, Numpy: To define the numerical array and matrixPandas: To handle and operate on dataStatsmodels: To handle parameter estimation & statistical testingPylab: To generate plotsYou can install above libraries using pip by running below command in ... Read More
There are two possibilities to check if MongoDB database exists.Case 1: The first possibility is that the MongoDB database exists i.e. it returns particular index.Case 2: The second possibility is that the MongoDB database does not exist i.e. it returns index -1.NOTE: An index starts from 0 and ends with (N-1) like an array.The syntax is as follows to check if MongoDB database exists.db.getMongo().getDBNames().indexOf("yourDatabaseName");Case 1: Let us implement the above syntax to check if MongoDB database exists. Following is the querydb.getMongo().getDBNames().indexOf("test");This will produce the following output6Look at the above sample output, we are getting 6 that means the database “test” ... Read More
Let’s say the following is our string with integer and characters −String str = "(29, 12; 29, ) (45, 67; 78, 80)";Now, to extract integers, we will be using the following pattern −\dWe have set it with Pattern class −Matcher matcher = Pattern.compile("\d+").matcher(str);Example Live Demoimport java.util.ArrayList; import java.util.List; import java.util.regex.Matcher; import java.util.regex.Pattern; public class Demo { public static void main(String[] args) { String str = "(29, 12; 29, ) (45, 67; 78, 80)"; Matcher matcher = Pattern.compile("\d+").matcher(str); Listlist = new ArrayList(); while(matcher.find()) { list.add(Integer.parseInt(matcher.group())); } System.out.println("Integers = "+list); } }OutputIntegers = [29, 12, 29, 45, 67, 78, 80]
You can use modify command for this. Let us first us create a table.mysql> create table DemoTable ( StudentId varchar(200) not null, StudentName varchar(20), StudentAge int, StudentAddress varchar(20), StudentCountryName varchar(20) ); Query OK, 0 rows affected (0.73 sec)Now check the description of table.mysql> desc DemoTable;This will produce the following output −+--------------------+--------------+------+-----+---------+-------+ | Field | Type | Null | Key | Default | Extra | +--------------------+--------------+------+-----+---------+-------+ | StudentId | varchar(200) | NO | | NULL | ... Read More
A view of the ByteBuffer can be created as an IntBuffer using the asIntBuffer() method in the class java.nio.ByteBuffer. This method requires no parameters and it returns an int buffer as required. This buffer reflects the changes made to the original buffer and vice versa.A program that demonstrates this is given as follows −Example Live Demoimport java.nio.*; import java.util.*; public class Demo { public static void main(String[] args) { int n = 50; try { ByteBuffer bufferB = ByteBuffer.allocate(n); IntBuffer bufferI = bufferB.asIntBuffer(); ... Read More
This conditional operator is also known as the Ternary Operator. This operator has three phase.Exp1 ? Exp2 : Exp3;where Exp1, Exp2, and Exp3 are expressions. Notice the use and placement of the colon. The value of a ? expression is determined like this: Exp1 is evaluated. If it is true, then Exp2 is evaluated and becomes the value of the entire ? expression. If Exp1 is false, then Exp3 is evaluated and its value becomes the value of the expression.The ? is called a ternary operator because it requires three operands and can be used to replace if-else statements, which ... Read More
You can update the in exact element array in MongoDB with the help of below statement. The syntax is as follows:{"yourArrayDocumentName.$.yourNestedArrayDocument.yourPosition":"yourValue"}});To understand the above syntax, let us create a collection with some documents. The query to create a collection with document is as follows:> db.updateExactField.insertOne({"ActorId":1, "ActorDetails":[{"ActorName":"Johnny Depp", "MovieList": ["The Tourist", "Public Enemy"]}, ... {"ActorName":"Chris Evans", "MovieList":["Captain America", "Avengers"]}]}); { "acknowledged" : true, "insertedId" : ObjectId("5c6d7f63f2db199c1278e7f1") }Now you can display documents from a collection with the help of find() method. The query is as follows:> db.updateExactField.find().pretty();The following is the output:{ "_id" : ObjectId("5c6d7f63f2db199c1278e7f1"), "ActorId" : 1, ... Read More
When a Web server responds to an HTTP request, the response typically consists of a status line, some response headers, a blank line, and the document. A typical response looks like this −HTTP/1.1 200 OK Content-Type: text/html Header2: ... ... HeaderN: ... (Blank Line) ... ... The status line consists of the HTTP version (HTTP/1.1 in the example), a status code (200 in the example), and a very short message corresponding to the status code (OK in the example).Following is ... Read More
Before getting into example, we should know what sqlite data base in android is. SQLite is an open source SQL database that stores data to a text file on a device. Android comes in with built in SQLite database implementation. SQLite supports all the relational database features. In order to access this database, you don't need to establish any kind of connections for it like JDBC, ODBC etc.This example demonstrate about How to concat two or more columns with separator in Android sqlite.Step 1 − Create a new project in Android Studio, go to File ⇒ New Project and fill ... Read More
The average() method of the LongStream class in Java returns an OptionalDouble describing the arithmetic mean of elements of this stream, or an empty optional if this stream is empty.The syntax is as follows.OptionalDouble average()Here, OptionalDouble is a container object which may or may not contain a double value.To use the LongStream class in Java, import the following package.import java.util.stream.LongStream;Create LongStream and add elements.LongStream longStream = LongStream.of(100L, 150L, 180L, 200L, 250L, 300L, 500L);Get the average of the elements in the stream.OptionalDouble res = longStream.average();The following is an example to implement LongStream average() method in Java.Example Live Demoimport java.util.*; import java.util.stream.LongStream; public ... Read More