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Found 26504 Articles for Server Side Programming

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To create side by side histograms in base R, we first need to create a histogram using hist function by defining a larger limit of X-axis with xlim argument. After that we can create another histogram that has the larger mean and smaller standard deviation so that the bars do not clash with each other and add=T argument must also be added inside the second hist function.Example Live Demohist(rnorm(5000,mean=5,sd=2.1),col="green",xlim=c(1,20))OutputExamplehist(rnorm(5000,mean=15,sd=1.25),col="red",add=T)Output

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We can easily identify duplicate values in a matrix by using duplicated function but it does not specify that the first occurrence is also duplicated. Therefore, we need to use it with OR sign | and the argument fromLast = TRUE of duplicated function so that the first occurrence of the duplicated values will be also identified as duplicate.Example Live DemoM1

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Sometimes analysis requires the user to check if values in two columns of an R data frame are exactly the same or not, this is helpful to analyze very large data frames if we suspect the comparative values in two columns. This can be easily done with the help of ifelse function.ExampleConsider the below data frame − Live Demox1

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To create a regression line with 0 intercept and slope equals to 1 using ggplot2, we can use geom_abline function but we need to pass the appropriate limits for the x axis and y axis values. For example, if we have two columns x and y in a data frame df and both have ranges starting from -1 to 1 then the scatterplot with regression line with 0 intercept and slope equals to 1 can be created as −ggplot(df,aes(x,y))+geom_point()+geom_abline()+lims(x=c(-1,1),y=c(-1,1))ExampleConsider the below data frame − Live Demox

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When we receive data from any source, it is highly likely that it would not be a perfect data set for the intended analysis, therefore, we need to perform some cleaning or mining based on the characteristics of the data. For example, if we have a column name of a data frame as factor levels of a numerical variable then we might want to convert that data frame in such a way that numerical values are stored in a single column and the column names are stored in another column that will represent a factor so that we can apply ... Read More

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To perform the one-way anova with sample sizes having different sizes we can use aov function. Suppose we have a categorical column defined as Group with four categories and a continuous variable Response both stored in a data frame called df then the one-way anova can be performed as −aov(Response~Group,data=df)ExampleConsider the below data frame − Live DemoGroup

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A standard normal distribution is the type of distribution that has mean equals to zero with standard deviation 1. If we want to generate standard normal random numbers then rnorm function of R can be used but need to pass the mean = 0 and standard deviation = 1 inside this function.Example Live Demornorm(10, 0, 1)Output[1] 0.6936607 -0.7967657 -2.7544428 0.2688767 0.5278463 -1.5387568 [7] 1.1716632 -1.5033895 0.8112929 -1.0101065Example Live Demornorm(50, 0, 1)Output[1] 2.58246666 -0.53083341 -0.57343343 1.08172756 1.30341849 -0.07440422 [7] -0.41869305 -0.96227706 -0.46899119 1.55428279 0.09162738 -0.96027221 [13] -0.84735327 -1.74949782 0.58541758 0.23117630 0.47402479 -0.72453853 [19] 0.07171564 1.13088794 0.18735157 0.25091758 -1.34728315 -0.39768159 [25] -0.38109955 -0.34019286 -1.51778561 ... Read More

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Data analysis not only includes mathematical operations, we have to spend a lot of time in data cleaning, data mining, feature engineering etc. One operation could be removing list elements by their name if they are not helpful to achieve our objective. The removal of the elements by using their names can be done with the help of which function.ExampleConsider the below list Live DemoList1

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The width of the line chart can be increased by using size argument inside geom_line aesthetics of ggplot2. For example, if we have a data frame df that contains two numerical columns x and y, and we want to create a line chart between the two with larger width then it can be done as −ggplot(df)+geom_line(aes(x,y,size=2))ExampleConsider the below data frame − Live Demox