Transposing

Good! Matrices are widely used in math, starting with different geometrical transformations, and ending with neural networks (yes, matrices are commonly used in AI).

What if we have a matrix and want to 'rotate' it? (or vice versa)?

In math, this operation is called transposing. It swaps columns with rows. In R this operation is implemented under t() function. This function receives the matrix you want to transpose as the parameter. For example,

# Initial matrix

m <- matrix(1:6, nrow = 2)

m # Output initial matrix

# Output transposed matrix

t(m)


              123456
            
# Initial matrix
m <- matrix(1:6, nrow = 2)
m # Output initial matrix

# Output transposed matrix
t(m)

As you can see, the initial matrix was 2x3 (2 rows and 3 columns), and the transposed is 3x2.

Oppgave

Swipe to start coding

Given the matrix from the previous chapter.

Assign this matrix to the m variable.
Output the transposed m matrix.

Løsning

# Vector of numbers

num <- seq(2, 16, 2)

# Build a matrix

m <- matrix(num, nrow = 2, byrow = T)

# Output transposed matrix

t(m)

Alt var klart?

Takk for tilbakemeldingene dine!

Seksjon 1. Kapittel 3

# Vector of numbers

num <- seq(2, 16, 2)

# Build a matrix

___ <- matrix(num, nrow = 2, byrow = T)

# Output transposed matrix

___(___)