Get Index Positions of Multiple Minima & Maxima in Data Frame Column in R (2 Examples)
In this R tutorial you’ll learn how to identify the positions of multiple minima and maxima.
Creation of Example Data
data(iris) # Example data head(iris) # Sepal.Length Sepal.Width Petal.Length Petal.Width Species # 1 5.1 3.5 1.4 0.2 setosa # 2 4.9 3.0 1.4 0.2 setosa # 3 4.7 3.2 1.3 0.2 setosa # 4 4.6 3.1 1.5 0.2 setosa # 5 5.0 3.6 1.4 0.2 setosa # 6 5.4 3.9 1.7 0.4 setosa |
data(iris) # Example data head(iris) # Sepal.Length Sepal.Width Petal.Length Petal.Width Species # 1 5.1 3.5 1.4 0.2 setosa # 2 4.9 3.0 1.4 0.2 setosa # 3 4.7 3.2 1.3 0.2 setosa # 4 4.6 3.1 1.5 0.2 setosa # 5 5.0 3.6 1.4 0.2 setosa # 6 5.4 3.9 1.7 0.4 setosa
Example 1: Find Index of First Minimum or Maximum
which.min(iris$Petal.Width) # Applying which.min function # [1] 10 |
which.min(iris$Petal.Width) # Applying which.min function # [1] 10
which.max(iris$Petal.Width) # Applying which.max function # [1] 101 |
which.max(iris$Petal.Width) # Applying which.max function # [1] 101
Example 2: Find Indices of Every Minima or Maxima
which(iris$Petal.Width == min(iris$Petal.Width)) # Applying which & min # [1] 10 13 14 33 38 |
which(iris$Petal.Width == min(iris$Petal.Width)) # Applying which & min # [1] 10 13 14 33 38
which(iris$Petal.Width == max(iris$Petal.Width)) # Applying which & max # [1] 101 110 145 |
which(iris$Petal.Width == max(iris$Petal.Width)) # Applying which & max # [1] 101 110 145