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Operation with Matrices | Matrices
R Introduction: Part II
course content

Зміст курсу

R Introduction: Part II

R Introduction: Part II

1. Matrices
2. Data Frames
3. Lists

bookOperation with Matrices

Good! Now we know how to create and customize matrices. It's time to consider the operations we can perform with matrices.

You can perform basic math operations with matrices. Performing a basic operation between a matrix and a single number will perform the respective operation for all matrix elements. For example, for the given matrix below...

...we can multiply each element by 3.

1234567
# Vector of integers num <- 1:9 # Matrix m <- matrix(num, nrow = 3, ncol = 3, byrow = T) # Multiply each matrix element by 3 m * 3
copy

As you can see, each matrix element was multiplied by 3. You can also use mean() and sum() functions for matrices. These functions will return the overall mean or total value, respectively. For example,

1234
num <- 1:9 m <- matrix(num, nrow = 3, ncol = 3, byrow = T) # Calculate overall mean mean(m)
copy

Additionally, you can also apply these functions to rows or columns separately. These functions are rowSums(), rowMeans(), colSums(), colMeans(). I think it's obvious what each function does according to their names. For example, let's calculate the column sums.

1234
num <- 1:9 m <- matrix(num, nrow = 3, ncol = 3, byrow = T) # Columns sums colSums(m)
copy

Let's practice a bit.

Завдання

Given matrix named m.

Your tasks are:

  1. Divide each element by 2, then add 1. Reassign the result to the m variable.
  2. Output the matrix m.
  3. Output the columns totals of the m matrix.
  4. Output mean value of all m elements.

Switch to desktopПерейдіть на комп'ютер для реальної практикиПродовжуйте з того місця, де ви зупинились, використовуючи один з наведених нижче варіантів
Все було зрозуміло?

Як ми можемо покращити це?

Дякуємо за ваш відгук!

Секція 1. Розділ 6
toggle bottom row

bookOperation with Matrices

Good! Now we know how to create and customize matrices. It's time to consider the operations we can perform with matrices.

You can perform basic math operations with matrices. Performing a basic operation between a matrix and a single number will perform the respective operation for all matrix elements. For example, for the given matrix below...

...we can multiply each element by 3.

1234567
# Vector of integers num <- 1:9 # Matrix m <- matrix(num, nrow = 3, ncol = 3, byrow = T) # Multiply each matrix element by 3 m * 3
copy

As you can see, each matrix element was multiplied by 3. You can also use mean() and sum() functions for matrices. These functions will return the overall mean or total value, respectively. For example,

1234
num <- 1:9 m <- matrix(num, nrow = 3, ncol = 3, byrow = T) # Calculate overall mean mean(m)
copy

Additionally, you can also apply these functions to rows or columns separately. These functions are rowSums(), rowMeans(), colSums(), colMeans(). I think it's obvious what each function does according to their names. For example, let's calculate the column sums.

1234
num <- 1:9 m <- matrix(num, nrow = 3, ncol = 3, byrow = T) # Columns sums colSums(m)
copy

Let's practice a bit.

Завдання

Given matrix named m.

Your tasks are:

  1. Divide each element by 2, then add 1. Reassign the result to the m variable.
  2. Output the matrix m.
  3. Output the columns totals of the m matrix.
  4. Output mean value of all m elements.

Switch to desktopПерейдіть на комп'ютер для реальної практикиПродовжуйте з того місця, де ви зупинились, використовуючи один з наведених нижче варіантів
Все було зрозуміло?

Як ми можемо покращити це?

Дякуємо за ваш відгук!

Секція 1. Розділ 6
toggle bottom row

bookOperation with Matrices

Good! Now we know how to create and customize matrices. It's time to consider the operations we can perform with matrices.

You can perform basic math operations with matrices. Performing a basic operation between a matrix and a single number will perform the respective operation for all matrix elements. For example, for the given matrix below...

...we can multiply each element by 3.

1234567
# Vector of integers num <- 1:9 # Matrix m <- matrix(num, nrow = 3, ncol = 3, byrow = T) # Multiply each matrix element by 3 m * 3
copy

As you can see, each matrix element was multiplied by 3. You can also use mean() and sum() functions for matrices. These functions will return the overall mean or total value, respectively. For example,

1234
num <- 1:9 m <- matrix(num, nrow = 3, ncol = 3, byrow = T) # Calculate overall mean mean(m)
copy

Additionally, you can also apply these functions to rows or columns separately. These functions are rowSums(), rowMeans(), colSums(), colMeans(). I think it's obvious what each function does according to their names. For example, let's calculate the column sums.

1234
num <- 1:9 m <- matrix(num, nrow = 3, ncol = 3, byrow = T) # Columns sums colSums(m)
copy

Let's practice a bit.

Завдання

Given matrix named m.

Your tasks are:

  1. Divide each element by 2, then add 1. Reassign the result to the m variable.
  2. Output the matrix m.
  3. Output the columns totals of the m matrix.
  4. Output mean value of all m elements.

Switch to desktopПерейдіть на комп'ютер для реальної практикиПродовжуйте з того місця, де ви зупинились, використовуючи один з наведених нижче варіантів
Все було зрозуміло?

Як ми можемо покращити це?

Дякуємо за ваш відгук!

Good! Now we know how to create and customize matrices. It's time to consider the operations we can perform with matrices.

You can perform basic math operations with matrices. Performing a basic operation between a matrix and a single number will perform the respective operation for all matrix elements. For example, for the given matrix below...

...we can multiply each element by 3.

1234567
# Vector of integers num <- 1:9 # Matrix m <- matrix(num, nrow = 3, ncol = 3, byrow = T) # Multiply each matrix element by 3 m * 3
copy

As you can see, each matrix element was multiplied by 3. You can also use mean() and sum() functions for matrices. These functions will return the overall mean or total value, respectively. For example,

1234
num <- 1:9 m <- matrix(num, nrow = 3, ncol = 3, byrow = T) # Calculate overall mean mean(m)
copy

Additionally, you can also apply these functions to rows or columns separately. These functions are rowSums(), rowMeans(), colSums(), colMeans(). I think it's obvious what each function does according to their names. For example, let's calculate the column sums.

1234
num <- 1:9 m <- matrix(num, nrow = 3, ncol = 3, byrow = T) # Columns sums colSums(m)
copy

Let's practice a bit.

Завдання

Given matrix named m.

Your tasks are:

  1. Divide each element by 2, then add 1. Reassign the result to the m variable.
  2. Output the matrix m.
  3. Output the columns totals of the m matrix.
  4. Output mean value of all m elements.

Switch to desktopПерейдіть на комп'ютер для реальної практикиПродовжуйте з того місця, де ви зупинились, використовуючи один з наведених нижче варіантів
Секція 1. Розділ 6
Switch to desktopПерейдіть на комп'ютер для реальної практикиПродовжуйте з того місця, де ви зупинились, використовуючи один з наведених нижче варіантів
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