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Nizamuddin Siddiqui has Published 2307 Articles
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Nizamuddin Siddiqui
78 Views
To create a column of difference in data frames stored in R list, we can follow the below steps −First of all, create a list of data frames.Then, use lapply function to create a column of difference in data frames stored in the list.ExampleCreate the list of data framesUsing data.frame ... Read More
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Nizamuddin Siddiqui
846 Views
To combine two rows in data.table object in R by addition, we can follow the below steps −First of all, create a data.table object.Then, using plus sign (+) to add two rows and store the addition in one of the rows.After that, remove the row that is not required by ... Read More
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Nizamuddin Siddiqui
107 Views
To find the groupwise mean and groupwise sum at the same time, we can first convert the data frame into a data.table object and then apply the sum function and mean function for data.table object groups as shown in the below examples.Example 1Following snippet creates a sample data frame −GroupRead More
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Nizamuddin Siddiqui
433 Views
To minus every element of a vector with every element of another vector, we can use outer function by defining the subtraction sign.For example, if we have two vectors say x and y and we want to minus every element in x from every element in y then we can ... Read More
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Nizamuddin Siddiqui
67 Views
To create a column of total in data frames stored in R list, we can follow the below steps −First of all, create a list of data frames.Then, use lapply function to create a column of total in data frames stored in the list.ExampleCreate the list of data framesUsing data.frame ... Read More
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Nizamuddin Siddiqui
984 Views
To change the name of data frames stored in an R list, we can follow the below steps −First of all, create a list of data frames.Then, use names function to change the name of data frames.ExampleCreate the list of data framesUsing data.frame function to create data frames and list ... Read More
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Nizamuddin Siddiqui
95 Views
When we want to find the combinations of a vector elements, we can use combn function with size of the combination say 2 for pairs but the result gives space between the values. If we do not want to get the combinations with space then combn function will be used ... Read More
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Nizamuddin Siddiqui
805 Views
To find the cumulative sum for each row in an R data frame, we would need to read the data frame as a data.table object and then Reduce function will be used with accumulate argument.For Example, if we have a data frame called df and we want to find the ... Read More
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Nizamuddin Siddiqui
898 Views
To find the frequency of particular value in rows of an R data frame, we can use mutate function of dplyr package along with rowSums function.For example, if we have a data frame called df then we can find the number of 5’s in each row of df by using ... Read More