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Articles by Nizamuddin Siddiqui
Page 86 of 196
How to remove rows that contains all zeros in an R data frame?
Often, we get missing data and sometimes missing data is filled with zeros if zero is not the actual range for a variable. In this type of situations, we can remove the rows where all the values are zero. For this purpose, we can use rowSums function and if the sum is greater than zero then keep the row otherwise neglect it.Example1y1
Read MoreHow to create stacked barplot using barplot function in R?
To create a stacked barplot using barplot function we need to use matrix instead of a data frame object because in R barplot function can be used for a vector or for a matrix only. We must be very careful if we want to create a stacked bar plot using barplot function because bar plots are created for count data only. Here, you will see some examples of count as well as continuous data, carefully read the graphs and understand how the graphs are different from each other.Example1M1
Read MoreHow to extract the model equation from model object in R?
To extract the model equation model object, we can use the model object name with dollar sign and call function. For example, if we have a model object name Model then the model equation can be extracted by using Model$call. This will directly present the equation that was used to create the model.Example1x1
Read MoreHow to remove continuously repeated duplicates in an R data frame column?
Often values are repeated that generate duplication in the data and we might want to get rid of those values if they are not likely to create bias in the output of the analysis. For example, if we have a column that defines a process and we take the output of the process five times but it takes the same output all the time then we might want to use only one output.Example1ID
Read MoreHow to create relative frequency table using dplyr in R?
The relative frequency is the proportion of something out of total. For example, if we have 5 bananas, 6 guava, 10 pomegranates then the relative frequency of banana would be 5 divided by the total sum of 5, 6, and 10 that is 21 hence it can be also called proportional frequency.Example1y%mutate(freq=n/sum(n)) `summarise()` ungrouping output (override with `.groups` argument) # A tibble: 2 x 3Outputy n freq 1 Female 11 0.55 2 Male 9 0.45 Warning message: `...` is not empty. We detected these problematic arguments: * `needs_dots` These dots only exist to allow future extensions and should be empty. Did you misspecify an argument?
Read MoreHow to create multiple lines chart with unique line types in R?
Line types can be very different and they are helpful to differentiate among different variables. Mostly, it is used to plot trend data so that the trend for different variables can be visualized with a unique line. In R, we can use matplot function to create such type of multiple lines chart.Example1M1
Read MoreHow to remove rows in an R data frame using row names?
There are a lot of ways to subset an R data frame and sometimes we need to do it by removing rows. In general, the rows are removed by using the row index number but we can do the same by using row names as well. This can be done by storing the row names that should be removed in a vector and then removing through subsetting with single square brackets as shown in the below examples.ExampleConsider the below data frame:> x y row.names(df) dfOutput x y A ...
Read MoreHow to find the sum of diagonal elements in a table in R?
The sum of diagonal elements could be required in matrix analysis therefore, we can convert the matrix into a table and find the sum of diagonal elements. This can be easily done by using sun function by extracting diagonal elements of the table using diag function. For example, if we have a table T then the sum of diagonal elements of T can be found as sum(diag(T)).ExampleTable1
Read MoreHow to create a function in R with two inputs?
To create a function with two inputs, we just need to provide two different arguments inside function. For example, if we want to create a function to find the square of a+b then we can use x and y inside function. Check out the below examples to understand how we can do it.Example1> F F(x=1, y=1) > F(x=2, y=3) > F(x=c(1, 2), y=c(2, 3))Output[1] 4 [1] 25 [1] 9 25Example> F(x=rpois(50, 2), y=rpois(50, 7))Output[1] 36 169 121 36 49 100 144 169 144 81 100 256 121 121 36 64 49 225 121 [20] 16 64 100 36 64 ...
Read MoreHow to find the intersection between two or more lists in R?
The intersection of lists means the elements that are unique and common between the lists. For example, if we have a list that contains 1, 2, 3, 3, 3, 2, 1 and the other list that contains 2, 2, 1, 2, 1 then the intersection will return only those elements that are common between the lists and also unique, hence for this example we will get 1 and 2. In R, we can do this by using intersection function along with Reduce function.Consider the below lists −ExampleList1
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