Data Structure

Data Structure - Matrix

Q

What is a Matrix?

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A

Matrix is an extension of vector into 2 dimensions

1. Create a matrix object with the matrix() function -

> m = matrix(1:20, nrow=5,ncol=4)
> m
     [,1] [,2] [,3] [,4]
[1,]    1    6   11   16
[2,]    2    7   12   17
[3,]    3    8   13   18
[4,]    4    9   14   19
[5,]    5   10   15   20

> typeof(m)
[1] "integer"

> is.matrix(m)
[1] TRUE

> is.vector(m)
[1] FALSE

2. Get matrix length, dimensions and members -

> m = matrix(1:20, nrow=5,ncol=4)

> length(m)
[1] 20

> dim(m)
[1] 5 4

> m[3,2]
[1] 8

⇒ Data Structure - Data Frame

⇐ Data Structure - Factor

⇑ R Language Basics

⇑⇑ R Software Environment - Frequently Asked Questions

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