# Is there a count function in R?

## Is there a count function in R?

That's just basic counting, which is easy with the count function from Hadley Wickham's excellent plyr package. Now, like a lot of R functions, the count help page is a bit intimidating. ... count package:plyr R Documentation Count the number of occurences.

## How do I count unique values in R?

How to Count Unique Data Values in R

1. Get the unique values of the variable using unique().
2. Get the length of the resulting vector using length().

## How do I count logical values in R?

1. To count TRUE values in a logical vector, you can use the following functions:
2. In vector where there are NA values:
3. The length function counts the return value of NA's as a TRUE value.
4. In vectors having no TRUE values:
5. So the best solution to count TRUE values is to use the sum() function along with the na.

## What %>% means in R?

The compound assignment %% operator is used to update a value by first piping it into one or more expressions, and then assigning the result. For instance, let's say you want to transform the mpg variable in the mtcars data frame to a square root measurement.

## What is not equal to in r?

The Inequality Operator != ). For example, the sentence "hello" != "goodbye" would read as: “hello” is not equal to “goodbye”. Because this statement is correct, R will output TRUE .

## What is the use of in R?

It is a convenience function designed that uses non-standard evaluation of its second argument. It's called non-standard because the unquoted characters following \$ are first quoted before being used to extract a named element from the first argument.

## What is the command to exit in R?

You can exit R with the quit() command. More succinctly, the quit command is aliased as q() . Normally when you start R, you'll be reminded of this command.

## How do you create a vector in R?

How to Create Vector in R? Vectors are generally created using the c() function. Since, a vector must have elements of the same type, this function will try and coerce elements to the same type, if they are different. Coercion is from lower to higher types from logical to integer to double to character.

## How do you access vector elements in R?

Vector elements are accessed using indexing vectors, which can be numeric, character or logical vectors. You can access an individual element of a vector by its position (or "index"), indicated using square brackets. In R, the first element has an index of 1. To get the 7th element of the colors vector: colors .

## How do I multiply a vector in R?

For example, if we have two vectors x and y each containing 1 and 2 then the multiplication of the two vectors will be 5. In R, we can do it by using t(x)%*%y.

## What is a scalar in R?

The simplest object type in R is a scalar. A scalar object is just a single value like a number or a name.

## How do you write transpose in R?

Rotating or transposing R objects That is, you transpose the rows and columns. You simply use the t() command. The result of the t() command is always a matrix object.

## Do matrices multiply in R?

R has two multiplication operators for matrices. The first is denoted by * which is the same as a simple multiplication sign. This operation does a simple element by element multiplication up to matrices. The second operator is denoted by %*% and it performs a matrix multiplication between the two matrices.

## What is solve in R?

solve() function in R Language is used to solve linear algebraic equation. Here equation is like a*x = b, where b is a vector or matrix and x is a variable whose value is going to be calculated. Syntax: solve(a, b)

## How do you add two matrices in R?

How can we add two matrices with different rows and columns in R?

1. You can transpose the 100x100 matrix, using t , then add the 1*100 matrix with as.numeric , then transpose the result. ...
2. Alternatively, you can expand the later one to the same shape as the former: temp1 + temp2[rep(1, nrow(temp1)), ] – mt1022 Sep 27 '18 at 10:53.

## What is matrix in R programming?

In R, a matrix is a collection of elements of the same data type (numeric, character, or logical) arranged into a fixed number of rows and columns. Since you are only working with rows and columns, a matrix is called two-dimensional. ... The third argument nrow indicates that the matrix should have three rows.

## How do you write a matrix in R programming?

To create a matrix in R you need to use the function called matrix() . The arguments to this matrix() are the set of elements in the vector. You have to pass how many numbers of rows and how many numbers of columns you want to have in your matrix. Note: By default, matrices are in column-wise order.

## How do you access a matrix in R?

We can access elements of a matrix using the square bracket [ indexing method. Elements can be accessed as var[row, column] . Here rows and columns are vectors.

## How do you add a matrix in R?

Matrix in R is formed using matrix, rbind, or cbind function. These functions have the following descriptions: matrix – used to transform a concatenated data into matrix form of compatible dimensions. rbind – short for row bind, that binds a concatenated data points of same sizes by row.

## What is Dimnames R?

The dimnames() command can set or query the row and column names of a matrix. Unlike rownames() or colnames() the dimnames() command operates on both rows and columns at once. If you use it to set the names you need to specify the names for the rows and columns in that order) in a list.

## How do I install a package in R?

Download and install a package (you only need to do this once). To use the package, invoke the library(package) command to load it into the current session....Adding Packages

1. Choose Install Packages from the Packages menu.
2. Select a CRAN Mirror. ...
3. Select a package. ...
4. Then use the library(package) function to load it for use.

## How does Rbind work in R?

rbind() function combines vector, matrix or data frame by rows. The column numbers of the two datasets must be the same, otherwise the combination will be meaningless. If two vectors do not have the same length, the elements of the short one will be repeated.

## How do I add multiple Dataframes in R?

Adding Rows To join two data frames (datasets) vertically, use the rbind function. The two data frames must have the same variables, but they do not have to be in the same order. If data frameA has variables that data frameB does not, then either: Delete the extra variables in data frameA or.

## What is a vector in R?

What are Vectors in R? A vector is the simplest type of data structure in R. Simply put, a vector is a sequence of data elements of the same basic type. Members of a vector are called Components. Here is a vector containing three numeric values 2, 3 and 5 : c(2, 3, 5)  2 3 5.

## What is the difference between Cbind and Rbind?

cbind() and rbind() both create matrices by combining several vectors of the same length. cbind() combines vectors as columns, while rbind() combines them as rows. ... As you will see, the cbind() function will combine the vectors as columns in the final matrix, while the rbind() function will combine them as rows.

## How do you set a Dataframe in R?

To combine a number of vectors into a data frame, you simple add all vectors as arguments to the data. frame() function, separated by commas. R will create a data frame with the variables that are named the same as the vectors used.

## How do I make a list in R?

How to create a list in R programming? List can be created using the list() function. Here, we create a list x , of three components with data types double , logical and integer vector respectively. Its structure can be examined with the str() function.

## What package is Rbind?

Functions cbind() and rbind() are defined in the mice package in order to enable dispatch to cbind. mids() and rbind. mids() when one of the arguments is a data.