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When we through two dices the sample space has thirty-six outcomes as shown below −(1,1),(1,2),(1,3),(1,4),(1,5),(1,6) (2,1),(2,2),(2,3),(2,4),(2,5),(2,6) (3,1),(3,2),(3,3),(3,4),(3,5),(3,6) (4,1),(4,2),(4,3),(4,4),(4,5),(4,6) (5,1),(5,2),(5,3),(5,4),(5,5),(5,6) (6,1),(6,2),(6,3),(6,4),(6,5),(6,6)Now, to create the sample space of throwing two dices in R, we can use the below mentioned command −expand.grid(1:6,1:6) ExampleTo create sample space of throwing two dices in R, use the command given below −expand.grid(1:6,1:6)OutputIf you execute the above given command, it generates the following output − Var1 Var2 1 1 1 2 2 1 3 3 1 4 4 1 5 5 1 6 6 1 7 1 2 8 2 2 9 3 2 10 4 2 11 5 2 12 6 2 13 1 3 14 2 3 15 3 3 16 4 3 17 5 3 18 6 3 19 1 4 20 2 4 21 3 4 22 4 4 23 5 4 24 6 4 25 1 5 26 2 5 27 3 5 28 4 5 29 5 5 30 6 5 31 1 6 32 2 6 33 3 6 34 4 6 35 5 6 36 6 6
To apply a mathematical operation such as multiplication, division, subtraction and addition on rows of an R data frame stored in a list, we can use apply function.For Example, if we have a list called LIST that contains a data frame df with two columns say X and Y and we want to add rows of df then we can use the command mentioned below −apply(df,1,function(x) x["X"]+x["Y"])Check out the Example given below to understand how it can be done.ExampleFollowing snippet creates a sample data frames: −x1
To remove dot at last position from every value in R data frame column, we can follow the below steps −First of all, create a data frame with a column having dot at last position in every value.Then, use gsub function to remove the dot at last position from every value in the column.ExampleCreate the data frameLet’s create a data frame as shown below −x
To find the position of minimum of each numerical column 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 minimum of each numerical column if some columns are categorical.Example 1Create the data frameLet’s create a data frame as shown below −factor1
To change the color of facet title using ggplot2 in R, we can use theme function with strip.text.x. argument.For Example, if we have a data frame called df that contains three columns say X, Y and F where F is a factor column then we can create facetted scatterplots between X and Y for values in F having different colored facet title by using the below mentioned command with facet title in different color −ggplot(df, aes(X, Y))+geom_point()+facet_wrap(~F)+theme(strip.text.x=element_text(colour="red"))ExampleFollowing snippet creates a sample data frame −PriceRead More
To multiply corresponding values from two matrices in R, we can follow the below steps −First of all, create two matrices.Then, use mapply function to multiply corresponding values from those two matrices.ExampleCreate the first matrixLet’s create a matrix as shown below −M1
To increase the space between facets in a facetted plot created by using ggplot2 in R, we can use theme function with panel.spacing argument.For Example, if we have a data frame called df that contains three columns say X, Y and F where F is a factor column then we can create facetted scatterplots having facets spaced at a larger distance between X and Y for values in F by using the command given below −ggplot(df, aes(X, Y))+geom_point()+facet_wrap(~F)+theme(panel.spacing=unit(1, "lines"))ExampleFollowing snippet creates a sample data frame −IVRead More
To multiply row values in a data.table object having multiple rows with single row data.table object in R, we can follow the below steps −First of all, create a data.table object with multiple rows and a data.table object with single row.Then, use mapply function to multiply row values in those objects.ExampleCreate the first data.table objectLet’s create a data.table object as shown below −library(data.table) x1
To change the color legend element border using ggplot2, we can use theme function where can put color in legend.key argument to desired color with element_rect.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 blue color of legend element border by using the command given below −ggplot(df, aes(IV, DV))+geom_point(aes(colour=factor(Class)))+theme(legend.key=element_rect(colour="red"))ExampleFollowing snippet creates a sample data frame −IVRead More
To change the sign of even number rows in a data.table object in R, we can follow the below steps −First of all, create a data.table object.Then, use vector multiplication with 1 and minus 1 to change the sign of even number rows.ExampleCreate the data.table objectLet’s create a data.table object as shown below −library(data.table) x