Find row and column index of maximum and minimum value in a matrix in R

In this article, we will discuss how to find the maximum and minimum value in any given matrix and printing its row and column index in the R Programming language.

**Example:**

Input:11 -9 36 20 1 81 13 99 77Output:maximum value: 99 row col 3 2 minimum value: -9 row col 1 2

### Finding Maximum value:

- In the code below, we have created a sample matrix, in which we have passed “
**nrow=3**“(matrix will have only 3 rows) in example 1 and “**ncol=2**“(matrix will have only 2 columns) in example 2. - Then we have printed the sample matrix in the next line with the message “Sample Matrix”.
- Then we have used the syntax below to find the row and column number of the maximum element and stored it in the variable “max”.
**We have made use of the max() function which is used to find the maximum element present in an object**. This object can be a Vector, a list, a matrix, a data frame, etc. **The**“**which()” function is used to get the index or position of the value which satisfies the given condition**. Then we have printed the maximum value along with its row and column index.

Syntax: which(m == max(m), arr.ind=TRUE)

**Example 1:**

## R

`# defining a sample matrix` `m = ` `matrix` `(` `c` `(11, 20, 13, -9, 1, 99, 36, 81, 77), ` ` ` `nrow = 3) ` ` ` `print` `(` `"Sample Matrix:"` `)` `print` `(m)` ` ` `# stores indexes of max value ` `max = ` `which` `(m == ` `max` `(m), arr.ind = ` `TRUE` `) ` `print` `(` `paste` `(` `"Maximum value: "` `, m[max]))` `print` `(max)` |

**Output:**

[1] "Sample Matrix:" [,1] [,2] [,3] [1,] 11 -9 36 [2,] 20 1 81 [3,] 13 99 77 [1] "Maximum value: 99" row col [1,] 3 2

**Example 2:**

## R

`# defining a sample matrix` `m = ` `matrix` `(` `c` `(1:16), ncol = 2) ` `print` `(` `"Sample Matrix:"` `)` `print` `(m)` ` ` `# stores indexes of max value` `max = ` `which` `(m == ` `max` `(m), arr.ind=` `TRUE` `) ` `print` `(` `paste` `(` `"Maximum value: "` `,m[max]))` `print` `(max)` |

**Output:**

[1] "Sample Matrix:" [,1] [,2] [1,] 1 9 [2,] 2 10 [3,] 3 11 [4,] 4 12 [5,] 5 13 [6,] 6 14 [7,] 7 15 [8,] 8 16 [1] "Maximum value: 16" row col [1,] 8 2

### Finding Minimum value:

- In the code below, we have created a sample matrix, in which we have passed “
**nrow=3**“(matrix will have only 3 rows) in example 1 and “**ncol=8**“(matrix will have only 8 columns) in example 2 as a parameter while defining the matrix. - Then we have printed the sample matrix in the next line with the message “Sample Matrix”.
- Then we have used the syntax below to find the row and column number of the minimum element and stored it in the variable “min”.
**We have made use of the min() function which is used to find the minimum element present in an object.**This object can be a Vector, a list, a matrix, a data frame, etc. **The “which()” function is used to get the index or position of the value which satisfies the given condition.**Then we have printed the minimum value along with its row and column index.

Syntax: which(m == min(m), arr.ind=TRUE)

**Example 1:**

## R

`# defining a sample matrix` `m = ` `matrix` `(` `c` `(11, 20, 13, -9, 1, 99, 36, 81, 77), nrow = 3) ` `print` `(` `"Sample Matrix:"` `)` `print` `(m)` ` ` `# stores indexes of min value` `min = ` `which` `(m == ` `min` `(m), arr.ind = ` `TRUE` `) ` `print` `(` `paste` `(` `"Minimum value: "` `, m[min]))` `print` `(min)` |

**Output:**

[1] "Sample Matrix:" [,1] [,2] [,3] [1,] 11 -9 36 [2,] 20 1 81 [3,] 13 99 77 [1] "Minimum value: -9" row col [1,] 1 2

**Example 2:**

## R

`# defining a sample matrix` `m = ` `matrix` `(` `c` `(1:16), ncol = 8) ` `print` `(` `"Sample Matrix:"` `)` `print` `(m)` ` ` `# stores indexes of min value ` `min = ` `which` `(m == ` `min` `(m), arr.ind = ` `TRUE` `) ` `print` `(` `paste` `(` `"Minimum value: "` `, m[min]))` `print` `(min)` |

**Output:**

[1] "Sample Matrix:" [,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [1,] 1 3 5 7 9 11 13 15 [2,] 2 4 6 8 10 12 14 16 [1] "Minimum value: 1" row col [1,] 1 1