Found 2038 Articles for R Programming

How to combine two vectors by separating with different special characters in R?

Nizamuddin Siddiqui
Updated on 12-Aug-2020 09:33:49

90 Views

The combination of two vectors is used for many purposes such as performing two-way ANOVA, presenting data table, or making visual representation of the data. The combinations can be created with many special characters in R by using paste and rep function.ExampleConsider the below vectors Class and Names.> Class Class [1] "Stats" "Maths" "Chem" "Physics" "O-R" > Names Names [1] 101 102 103 104 105Suppose we want to combine Class and Names in a way that the new vector contains Stats|101, Stats|102, and so on. Also, we want to do the same with different special characters.We can do this by ... Read More

How to convert data frame values to a vector by rows in R?

Nizamuddin Siddiqui
Updated on 12-Aug-2020 07:26:11

499 Views

Data can be supplied to us in any form but it is possible that it is not the appropriate one that should be used for analysis. Sometimes data is recorded in a data frame but we might need it as a vector. In such type of situation, we have to change the values of our data frame in a vector. This can be done by reading the data frame values by reading them as.vector after transposing the data frame with t.ExampleConsider the below data frame −> x1 x2 x3 df df   x1  x2 x3  1 1  1  5  2 ... Read More

How to deal with error “$ operator is invalid for atomic vectors” in R?

Nizamuddin Siddiqui
Updated on 12-Aug-2020 07:20:15

2K+ Views

This error occurs because $ operator is not designed to access vector elements. If we use $ operator to access the vector elements then R does not understand it and consider it invalid, therefore, we must be very careful about where we should use $ operator. It happens when we give a name to our elements and start thinking that we can treat them as data frame columns which is a wrong approach. To access the vector elements, we should use single square brackets.ExampleConsider the below vector −> set.seed(1) > x1 x1 [1] 9 4 7 1 2 7 2 ... Read More

How to write strings with new lines in R?

Nizamuddin Siddiqui
Updated on 11-Aug-2020 14:35:54

290 Views

While writing the string vectors, we get them in a single line but we might want to represent strings in different lines especially in cases where each of the value of the string vector has a different meaning. This is helpful to the programmer as well as to any other reader. We can change the single line to multiple new lines using writeLines function in R.ExampleReading with single line −> String1 String1 [1] "Covid-19" "2020" "Lockdown" "Quarantine" "Life Changing"Reading the same vector with new lines −> String1 String2 writeLines(String2) Tutorialspoint SIMPLY EASY LEARNING You are browsing the best resource for ... Read More

How to check whether a vector contains an NA value or not in R?

Nizamuddin Siddiqui
Updated on 11-Aug-2020 14:34:24

2K+ Views

An NA value in R represents “Not Available” that means missing value. If a vector has even one NA value then the calculations for that vector becomes a little difficult because we will either have to remove that NA, replace it or neglect it during the calculations. To do any of these things, we will have to make some changes in our codes therefore, it is better to check whether a vector contain an NA or not before doing anything. This can be done with the help of any function in conjunction with is.na.Example> x1 x1 [1] 1 2 3 ... Read More

How to move a column from other position to first position in an R data frame?

Nizamuddin Siddiqui
Updated on 11-Aug-2020 14:31:05

218 Views

A column’s position in an R data frame is crucial specially when we are dealing with a large data set. As the first column appears first, it becomes necessary that we should have columns of the data frame in an order that helps us to look at the important columns easily. For this purpose, we might want to change the position of columns. To change the position of a column to first position we can use single square brackets.ExampleConsider the below data frame −> set.seed(99) > x1 x2 x3 x4 x5 x6 df df x1 x2 x3 x4 x5 x6 ... Read More

How to select random elements from an R vector?

Nizamuddin Siddiqui
Updated on 11-Aug-2020 14:26:06

8K+ Views

Random selection of elements from a R vector ensures the unbiased selection because while doing the random selection, each of the elements of the vector gets an equal probability of being selected by the random selection procedure specifically the simple random sampling selection procedure. To select, one or more elements randomly from an R vector, we can use sample function.Example> x1 x1  [1]  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 [26] 26 27 28 29 30 31 32 33 34 35 36 ... Read More

How to change a column in an R data frame with some conditions?

Nizamuddin Siddiqui
Updated on 11-Aug-2020 14:07:43

449 Views

Sometimes, the column value of a particular column has some relation with another column and we might need to change the value of that particular column based on some conditions. We need to make this change to check how the change in the values of a column can make an impact on the relationship between the two columns under consideration. In R, we can use single square brackets to make the changes in the column values.ExampleConsider the below data frame −> set.seed(1) > x1 x2 x3 df df x1 x2 x3 1 4 4 4.462839 2 4 1 3.941181 3 ... Read More

How to increase the length of an R data frame by repeating the number of rows?

Nizamuddin Siddiqui
Updated on 11-Aug-2020 13:43:01

453 Views

If we strongly believe that new data collection will result in the same type of data then we might want to stretch our data frame in R with more rows. Although, this is not recommended because we lose unbiasedness in the data due to this process but it is done to save time and money that will be invested in new data collection. In R, we can use rep with seq_len function to repeat the number of rows of an R data frame.ExampleConsider the below data frame −> x1 x2 df df x1 x2 1 Fruits 2 2 Vegetables 5 ... Read More

How to find group-wise summary statistics for an R data frame?

Nizamuddin Siddiqui
Updated on 11-Aug-2020 13:37:38

408 Views

To compare different groups, we need the summary statistics for each of the groups. It helps us to observe the differences between the groups. The summary statistics provides the minimum value, first quartile, median, third quartile, and the maximum values. Therefore, we can compare each of these values for the groups. To find the group-wise summary statistics for an R data frame, we can use tapply function.ExampleConsider the below data frame −> set.seed(99) > x1 x2 df head(df, 20) x1 x2 1 48 G1 2 33 G2 3 44 G3 4 22 G4 5 99 G5 6 62 G1 7 ... Read More

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