When we sort a data frame column in R, the row names are lost but we might need them. Therefore, sorting without losing row names is required and it can be done with the help of order function. For example, if we have a data frame called df that has a column x then sorting of x without losing row names can be done by using the below command −df[order(df$x),,drop=FALSE]Consider the below data frame −Example Live Demox1

When we matrices of larger size and the data is expected to from the same distribution or from same sources then we might expect that the matrices are equal. In this type of situations, we would like to check whether the two matrices are equal or not. This can be done with the help of all.equal function as shown in the below examples.Example Live DemoM1

To display 0 at Y-axis, we can set the limits for Y-axis using scale_y_continuous function of ggplot2 package. For example, if we have two columns say x and y in an R data frame called df then the scatterplot with displaying 0 at Y-axis can be created by using the below commandggplot(df,aes(x,y))+geom_point()+scale_y_continuous(limits=c(0,”upperlimit”))Consider the below data frame −Example Live Demox

To create boxplot using ggplot2 without whiskers, we need to use coef argument inside geom_boxplot function. For example, if we have data frame called df and there exists one categorical variable x and one response variable y then the boxplots for categories without whiskers can be created by using ggplot(df,aes(x,y))+geom_boxplot(coef=0).Consider the below data frame −Example Live Demox

If we have two vectors say x and y, x contains 1, 6 and y contains 5,10 then the sequence of values between these two vectors will be 1, 2, 3, 4, 5 and 6, 7, 8, 9, 10. Here the sequence is created by using the corresponding elements in x and y. To do this in R, we can use mapply function as shown in the below examples.Example Live Demox1

The first quartile is the value that exists at the 25th percentile, that means there are 25% of values in the data that lie below first quartile. When we find the summary of data frame the output returns this value but if we want to extract only the first quartile then quantile function can be used by specifying the percentage using 0.25.Consider the below data frame −Example Live Demox

The length of the largest string can be found with the help of max function combined with nchar function. For this purpose, we first need to access the appropriate column that contains string values. Suppose, we have a data frame called df that contains a string column defined as CHAR then the length of the largest string will be found by using the command max(nchar(df$CHAR)).Consider the below data frame −Example Live Demox

If we have a column that is key that means we want to use that column as an independent variable and find the statistical values such as sum, mean, standard deviation, range, etc. for the dependent variable. This can be done with the combination of with and tapply function as shown in the below examples.Consider the below data frame −Example Live Demox1

To extract unique values in multiple columns in an R data frame, we first need to create a vector of the column values but for that we would need to read the columns in matrix form. After that we can simply unique function for the extraction. To understand how it works check out the below examples.Consider the below data frame −Example Live Demox1

The splitting of comma separated values in an R vector can be done by unlisting the elements of the vector then using strsplit function for splitting. For example, if we have a vector say x that contains comma separated values then the splitting of those values will be done by using the command unlist(strsplit(x,",")).Example Live Demox1