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To change the row order in an R data frame, we can use single square brackets and provide the row order at first place.For example, if we have a data frame called df that contains 10 rows then we can change the row order by using the command given below −df[c(6:8,2,5,9,10,1,3:4),]Check out the below examples to understand how it works.Example 1Following snippet creates a sample data frame −x1
If we have a string column in an R data frame and the strings are mixed with numbers and we want to find the number of characters in each row of the string column then nchar function can be used with gsub function as shown in the below examples.Since R is case sensitive, we need to make sure that we use correct notation for small and upper-case letters while doing this type of analysis.Example 1Following snippet creates a sample data frame −x
To create histogram like plot with different color of bars, we can use col argument and provide the range up to the number of bars we expect in the histogram like plot.For example, if we have a vector of length 10 called X then we can create histogram like plot of X with different color of bars using the command given below −plot(X,type="h",col=1:10,lwd=5)Check out the below example to understand how it works.ExampleTo create histogram like plot with different color of bars, use the following command −x
To randomly split a vector into n vectors of different lengths, we can use sample function and set the repl argument to TRUE.For example, if we have a vector called X of size 100 then we can split it randomly into 10 vectors of different lengths by using the below command −split(X,sample(10,100,repl=TRUE))Example 1To randomly split a vector into n vectors of different lengths, use the following code −x
To scale some columns in data.table object in R, we can follow the below steps −First of all, create a data.table object.hen, subset the columns with single square brackets and use lapply, list and scale function to scale those columns.ExampleCreate the data.table objectLet’s create a data.table object as shown below −library(data.table) var1
To unsplit a split in R data frame, we can follow the below steps −First of all, create a data frame.Then, use split function to split the data frame.After that, use do.call function along with rbind function unsplit the data frame.ExampleCreate the data frameLet’s create a data frame as shown below −x
If we have a data frame where row indices are not in correct sequence then we can set them to NULL to get the correct sequence of row numbers starting from 1.For example, if we have a data frame called df which has row ordered in an inappropriate way then we can reorder the row indices in correct order by using the command given below −row.names(df)
To print the exact values of all elements in a column of an R data frame, we can follow the below stops −First of all, create a data frame.Then, use options function and provide the required number of digits for printing.ExampleCreate the data frameLet’s create a data frame as shown below −x
To change the color code of corrplot, we can use colorRampPalette function inside corrplot function. We can provide different colors in colorRampPalette that we want to display in the corrplot.Check out the below given example to understand how it can be done.ExampleFollowing snippet creates a sample data frame −x
To convert values greater than a threshold into 1 in matrix in R data frame, we can follow the below steps −First of all, create a matrix.Then, use ifelse function to convert values greater than a threshold into 1.ExampleCreate the matrixLet’s create a matrix as shown below −M