You can use the pmax() and pmin() functions in R to find the parallel maximum and minimum values, respectively, across multiple vectors.
These functions uses the following basic syntax:
pmax(vector1, vector2, vector3, ...) pmin(vector1, vector2, vector3, ...)
The following examples show how to use these functions with both vectors and data frames.
Example 1: Use pmax and pmin with Vectors
Suppose we have the following three vectors in R:
#define three vectors
vector1 <- c(2, 2, 3, 4, 5, 6, 9)
vector2 <- c(1, 2, 4, 3, 3, 5, 4)
vector3 <- c(0, 4, 3, 12, 5, 8, 8)
We can use the pmax and pmin functions to find the maximum and minimum values at corresponding elements across all three vectors:
#find max value across vectors
pmax(vector1, vector2, vector3)
[1] 2 4 4 12 5 8 9
#find min value across vectors
pmin(vector1, vector2, vector3)
[1] 0 2 3 3 3 5 4
Here’s how to interpret the output:
- The max value in the first position across all vectors was 2. The minimum value in the first position across all vectors was 0.
- The max value in the second position across all vectors was 4. The minimum value in the second position across all vectors was 2.
And so on.
Example 2: Use pmax and pmin with Data Frame Columns
Suppose we have the following data frame in R:
#create data frame
df <- data.frame(team=c('A', 'B', 'C', 'D', 'E'),
steals=c(24, 22, 36, 33, 30),
assists=c(33, 28, 31, 39, 34),
rebounds=c(30, 28, 24, 24, 41))
#view data frame
df
team steals assists rebounds
1 A 24 33 30
2 B 22 28 28
3 C 36 31 24
4 D 33 39 24
5 E 30 34 41
We can use the pmax and pmin functions to find the maximum and minimum values at corresponding elements across all three vectors:
#find max value across steals, assists, and rebounds columns
pmax(df$steals, df$assists, df$rebounds)
[1] 33 28 36 39 41
#find minimum value across steals, assists, and rebounds columns
pmin(df$steals, df$assists, df$rebounds)
[1] 24 22 24 24 30
Here’s how to interpret the output:
- The max value in the first row across the steals, assists, and rebounds columns was 33 and the minimum value was 24.
- The max value in the second row across the steals, assists, and rebounds columns was 28 and the minimum value was 22.
And so on.
Note: If you have missing values in any of the vectors, simply use the following syntax to ignore NA’s when calculating the maximum or minimum:
pmax(vector1, vector2, vector3, na.rm=TRUE) pmin(vector1, vector2, vector3, na.rm=TRUE)
Additional Resources
The following tutorials explain how to perform other common operations in R:
How to Use length() Function in R
How to Use cat() Function in R
How to Use substring() Function in R
