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Nizamuddin Siddiqui has Published 2307 Articles
![Nizamuddin Siddiqui](https://www.tutorialspoint.com/assets/profiles/218290/profile/60_42434-1594357075.jpg)
Nizamuddin Siddiqui
328 Views
If we have frequency data then we first need to find the total data or complete data by repeating the values up to the frequency corresponding to each value after that we can apply var function on this complete data.For Example, if we have a data frame called df that ... Read More
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Nizamuddin Siddiqui
4K+ Views
The autocorrelation plot or ACF plot is a display of serial correlation in data that changes over time. The ACF plot can be easily created by using acf function.For example, if we have a vector called V then we can create its autocorrelation plot by using the command acf(V). If ... Read More
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Nizamuddin Siddiqui
301 Views
To find the row mean of all matrices stored in an R list, we can use sapply function along with rowMeans function.For example, if we have a list called LIST that contains some matrices then the row means for each matrix can be found by using the following command −sapply(LIST, ... Read More
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Nizamuddin Siddiqui
1K+ Views
If we have frequency data then we first need to find the total data or complete data by repeating the values up to the frequency corresponding to each value after that we can apply median function on this complete data.For Example, if we have a data frame called df that ... Read More
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Nizamuddin Siddiqui
4K+ Views
To find the sample size for t test, we can use pwr.t.test function of pwr package, wherever we can pass the arguments for alternative hypothesis such as one-sided or two-sided, significance level, power of the test and difference for two samples.Check out the below examples to understand how it works.Example ... Read More
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Nizamuddin Siddiqui
96 Views
If we have multiple vectors and we want to combine the vector elements alternatively then we can use rbind function along with c function.For Example, if we have three vectors say X, Y, and Z as −X = 1, 2, 3 Y = 4, 5, 6 Z = 7, 8, ... Read More
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Nizamuddin Siddiqui
1K+ Views
The factor with duplicate levels represents grouping data but if we want to convert the grouping data into nominal data then duplicate values must be removed or converted into unique values. To make duplicate factor levels unique in an R data frame, we can use make.unique function.Check out the below ... Read More
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Nizamuddin Siddiqui
3K+ Views
We sometimes need to perform mathematical operations on all values in the data set. One such operation could be dividing each value by 100.For example, if we have a data frame called df then we can divide each value in df by 100 by using the below command −df[, 1:ncol(df)]/100ExampleFollowing ... Read More
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Nizamuddin Siddiqui
81 Views
To find the groupwise common value for a data.table object, we can use Reduce function with intersect function.For example, if we have a data.table object called DT that contains a numerical column say Num and a categorical column say C where C exists at the first position then the groupwise ... Read More
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Nizamuddin Siddiqui
415 Views
To find the frequency of exclusive group combinations in an R data frame, we can use count function of dplyr package along with ungroup function.For Example, if we have a data frame called df that contains four grouping columns say Grp1, Grp2, Grp3, and Grp4 then we can count the ... Read More