To find the square root of each value in columns if some columns are categorical in R data frame, we can follow the below steps −First of all, create a data frame.Then, use numcolwise function from plyr package to find the square root of each value in columns if some columns are categorical.ExampleCreate the data frameLet’s create a data frame as shown below −Level

To display legend on top using ggplot2 in R, we can use theme function with legend.justification argument to top.For Example, if we have a data frame called df that contains three columns say X and Y and F where X and Y are numerical and F is categorical then we can create scatterplot between X and Y with point colored by values in F by using the command given below −ggplot(df,aes(X,Y))+geom_point(aes(colour=factor(F)))+theme(legend.justification="top")ExampleFollowing snippet creates a sample data frame −x

By default, the text size of axes titles are small but if we want to increase that size so that people can easily recognize them then theme function can be used where we can use axis.title.y argument for Y-axis and axis.title.x argument for X-axis with element_text size to larger value.Check out the Example given below to understand how it can be done.ExampleFollowing snippet creates a sample data frame −Country

To find the column minimum if some columns are categorical in R data frame, we can follow the below steps −First of all, create a data frame.Then, use numcolwise function from plyr package to find the column minimum if some columns are categorical.ExampleCreate the data frameLet’s create a data frame as shown below −Group

To increase the width of axes tick (both X-axis and Y-axis at the same time) using ggplot2 in R, we can use theme function with axis.ticks argument where we can set element_line argument size to a larger value.For Example, if we have a data frame called df that contains a single column X and we want to create histogram of X with wider axes ticks then we can use the command given below −ggplot(df,aes(X))+geom_histogram(bins=30)+theme(axis.ticks=element_line(size=2))ExampleFollowing snippet creates a sample data frame −x

To find the row median of columns having same name in R data frame, we can follow the below steps −First of all, create a data frame with some columns having same name.Then, use tapply along with colnames and median function to find the row median of columns having same name.ExampleCreate the data frameLet’s create a data frame as shown below −df

To increase the width of axes (both X-axis and Y-axis at the same time) using ggplot2 in R, we can use theme function with axis.line argument where we can set element_line argument to a larger value.Check out the Example given below to understand how it can be done.ExampleFollowing snippet creates a sample data frame −x

To change the border style of a plot using ggplot2 in R, we can use theme function with panel.border argument where we can change the linetype for the plot border using element_rect. There are many linetypes and we can use them as desired.Check out the Example given below to understand how it can be done.ExampleFollowing snippet creates a sample data frame −x

To convert first letter into capital in single column data frame in R, we can follow the below steps −First of all, create a data frame with string column.Then, use sub function along with mutate function of dplyr package to convert first letter into capital in string column.ExampleCreate the data frameLet’s create a data frame as shown below −Names

To find the column name that contains value greater than a desired value in each row of an R data frame, we can use apply function along with lapply function.For Example, if we have a data frame called df and we want to extract column names for each row having values greater than 5 then we can use the command given below −lapply(apply(df,1, function(x) which(x5)),names)Example 1Following snippet creates a sample data frame −x1