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If we have a matrix that contains character columns and we want to convert a single column to numeric then we first need to convert the matrix into a data frame using as.data.frame function after that as.numeric function can be used to change the particular column to numeric type as shown in the below examples.Example 1Following snippet creates a matrix −M1
To find the average of a particular column in R data frame, we can take the help of delta ($) operator.For example, if we have a data frame called df that contains a column x then we can find the average of column x by using the command given below −mean(df$x)Example 1Following snippet creates a sample data frame −x1
To find the mean of all matrices stored in an R list, we can use sapply function along with mean function. For example, if we have a list called LIST that contains some matrices then the mean of each matrix can be found by using the command given below −sapply(LIST,mean)Check out the below given example to understand how it works.ExampleFollowing snippet creates a list of matrices −M1
To update single value in an R data frame, we can use row and column indices with single square brackets.For example, if we have a data frame called df that contains two columns and ten rows and if we want to change the fifth value in second column to 10 then we can use the command given below −df[5,2]
The coordinate of a value in an R matrix is the row and column intersection that is the row and column index for that particular value. This can be found by using which function.For example, if we have a matrix called M that contains value starting from 1 to 20 then we can find the coordinate of value 5 by using the command given below − which(M==5,arr.ind=TRUE)ExampleFollowing snippet creates a matrix −M1
Let us understand what a hardware firewall is.Hardware FirewallHardware firewalls are frequently built within the base of broadband routers and are an essential part of a network setup, particularly on a broadband connection. A hardware firewall can be very adequate with minimal or no configuration and can guard each device on the local network. It facilitates packet filtering to test a packet’s header for source and destination analysis, which data is then compared with a group of pre-defined security rules.The packet will be forwarded if it meets the rules or is dropped. Although any user with some computer knowledge can ... Read More
Let us begin by learning about VPN.VPNVPN stands for the virtual private network. It is an encrypted connection over the web from a device to a network. The encrypted connection supports that sensitive information is safely communicated. It avoids an unauthorized person from eavesdropping on the traffic and enables the user to organize work remotely. VPN technology is broadly used in corporate environments.A VPN protects your IP address by allowing the network to redirect it through a particularly configured remote server run by a VPN host. This defines that if you surf online with a VPN, the VPN server becomes ... Read More
Anycast is a method for routing network traffic where the sender distributes packets to a destination that is adjacent to it in terms of network topology. The features of Anycasting is that the networking approach can allow for messages to be shared to a team of receivers that all have the similar destination address.The Anycast method is one address and routing methodology compared with others including unicasting. Unicast facilitates a one-to-one connection between a server and a destination address. There are different procedures like multicast and broadcast that send signals from one point to multiple points.Anycasting is ruled by the ... Read More
Let us begin by understanding what WEP is.WEPWEP stands for Wired Equivalent Privacy. It is the generally used Wi-Fi security protocol in the world. WEP was produced as a Wi-Fi security requirement in 1999, September.The first form of WEP was not especially strong, even for the time they were launched, because U.S. regulation on the export of several cryptographic technologies led to manufacturers confining their devices to only 64-bit encryption. When the condition was lifted, it was raised to 128-bit. In spite of the introduction of 256-bit WEP, 128-bit remains one of the most common implementations.WEP was destined to support ... Read More
A web page is described as a single file or a singular page of any website. Each webpage is connected to a specific URL address used to render or access that specific page. These URLs and web pages can be private or public, based on how the developers have set up them.Some web browsers can be used to operate URLs, which can also be copied and shared by users. Viewing a website does not generally require some navigation if it can have its URL address. However, some URLs are attached to a website that facilitates developers to make a suitable ... Read More