Server Side Programming Articles - Page 1579 of 2646

Runnable and Callable both functional interface. Classes which are implementing these interfaces are designed to be executed by another thread.Thread can be started with Ruunable and they are two ways to start a new thread: one is by subclassing Thread class and another is implementing Runnable interface.Thread class does not have constructor for callable so we should use ExecutorService  class for executing thread.Sr. No.KeyRunnableCallable1PackageIt belongs to Java.langIt belongs to java.util.concurrent2Thread CreationWe can create thread by passing runnable as a parameter.We can’t create thread by passing callable as parameter  3Return TypeRuunable does not return anythingCallable can return results4.MethodIt has run() methodIt ... Read More

Java Collections framework is used for storing and manipulating group of data. It is an in-memory data structure and every element in the collection should be computed before it can be added in the collections.Stream API is only used for processing group of data. It does not modify the actual collection, they only provide the result as per the pipelined methods.Sr. No.KeyCollectionsStreams1BasicIt is used for storing and manipulating group of dataStream API is only used for processing group of data2PackageAll the classes and interfaces of this API is in the Java.util packageAll the classes and interfaces of this API is ... Read More

When the number of categories is large in numbers for a variable and we want to create a bar plot then the display of the bar plot becomes a little ambiguous because the bars are plotted very close to each other. To make the bars clearly visible, we can reduce the width of the bars and set different colors for them to make them visually attractive.geom_bar(width=0.2,color="red")Consider the below data frame −x

When we find the summary statistics of a data frame then the output is returned as a table and each of the column records the minimum, first quartile, median, median, third quartile, and maximum with their names. If we want to save this summary as a data frame then it is better to calculate it with apply function and store it as data.frame.ExampleConsider the below data frame − Live Demox1

In data analysis, often we require to determine the minimum and maximum values because these values help us to understand the limits of a column or variable under consideration. This can be done by using which.max for maximum and which.min for minimum with single square brackets to extract the rows.ExampleConsider the below data frame − Live Demox1

When we join or combine plots using grid.arrange the scales of the first plot comes in between as X-axis even if the independent variable in both of the plots is same.Therefore, we might want to remove the space between the plots while joining to get only one X-axis. This can be done by using theme function.ExampleConsider the below data frame − Live Demoset.seed(123) x

When we create a plot in R and draw gridlines then the gridlines are drawn on the basis of the values provided inside the grid function, therefore, it may or may not match with the Y-axis labels. But it can be done, we just need to set the values inside the grid function to NULL.ExampleConsider the below plot − Live Demox

Sometimes we need to create extra variable to add more information about the present data because it adds value. This is especially used while we do feature engineering. If we come to know about something that may affect our response then we prefer to use it as a variable in our data, hence we make up that with the data we have. For example, creating another variable applying conditions on other variable such as creating a binary variable for goodness if the frequency matches a certain criterion.ExampleConsider the below data frame − Live Demoset.seed(100) Group

Often, we need to find the power of a value or the power of all values in an R vector, especially in cases when we are dealing with polynomial models. This can be done by using ^ sign as we do in Excel. For example, if we have a vector x then the square of all values in x can be found as x^2.Example Live Demox1

The default position of axes titles in any software or programming language for any 2D graph is bottom for X-axis and left for Y-axis but we might to change the position of these titles to top and right respectively. This can be done by using scale_x_continuous(position="top") and scale_y_continuous(position="right") functions of ggplot2 package.ExampleConsider the below data frame − Live Demoset.seed(101) x