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R Introduction: Part II
R Introduction: Part II
What is a Matrix?
A matrix is a two-dimensional data structure in R, which means that every matrix element can be characterized by its position among rows and columns. Matrices in R can contain data of only one type, i.e., a matrix can not contain numbers and text simultaneously.
There are several ways to create a matrix in R. On one side, you can 'merge' two rows; on the other, you can 'merge' two columns. Let's consider each method separately. The first one is the rbind() function. Function name comes from Rows Bind - this function connects vectors as rows.
# Rows row_1 = c(1, 2, 3) row_2 = c(4, 5, 6) # Merge two rows rbind(row_1, row_2)
As you can see, this matrix has two rows and three columns (since each row has three values).
Another way - is to use cbind() function. Likewise, the previous function, name of this function comes from Columns Bind. Let's look at the example.
# Columns col_1 = c(1, 2, 3) col_2 = c(4, 5, 6) # Merge two columns cbind(col_1, col_2)
As you can see, this matrix has two columns and three rows (since each column has three values).
Swipe to start coding
Practice creating matrices by yourself using both methods!
- Create two vectors:
awith integers from1to4, andbwith integers from5to8using the colon:sign. - Create and output matrix by merging
aandbas rows. - Create and output matrix by merging
aandbas columns.
Løsning
Skift til skrivebord for at øve i den virkelige verdenFortsæt der, hvor du er, med en af nedenstående mulighederTak for dine kommentarer!
What is a Matrix?
A matrix is a two-dimensional data structure in R, which means that every matrix element can be characterized by its position among rows and columns. Matrices in R can contain data of only one type, i.e., a matrix can not contain numbers and text simultaneously.
There are several ways to create a matrix in R. On one side, you can 'merge' two rows; on the other, you can 'merge' two columns. Let's consider each method separately. The first one is the rbind() function. Function name comes from Rows Bind - this function connects vectors as rows.
# Rows row_1 = c(1, 2, 3) row_2 = c(4, 5, 6) # Merge two rows rbind(row_1, row_2)
As you can see, this matrix has two rows and three columns (since each row has three values).
Another way - is to use cbind() function. Likewise, the previous function, name of this function comes from Columns Bind. Let's look at the example.
# Columns col_1 = c(1, 2, 3) col_2 = c(4, 5, 6) # Merge two columns cbind(col_1, col_2)
As you can see, this matrix has two columns and three rows (since each column has three values).
Swipe to start coding
Practice creating matrices by yourself using both methods!
- Create two vectors:
awith integers from1to4, andbwith integers from5to8using the colon:sign. - Create and output matrix by merging
aandbas rows. - Create and output matrix by merging
aandbas columns.
Løsning
Skift til skrivebord for at øve i den virkelige verdenFortsæt der, hvor du er, med en af nedenstående mulighederTak for dine kommentarer!
Skift til skrivebord for at øve i den virkelige verdenFortsæt der, hvor du er, med en af nedenstående muligheder