R max() Function

R max() function is used to find the maximum value of a vector or data frame. For example,  if you have vec <- c(21, 19, 11, 2, 18, 3), then max(vec) will return 21.

This function can be used with any data type that is coercible to numeric, including logical vectors where TRUE is treated as 1 and FALSE as 0.

Syntax

max(input, na.rm = FALSE)

Parameters

  1. input: It is a  Vector or a data frame.
  2. na.rm: It removes the NA values; if it mentions FALSE, it considers NA, or if it mentioned TRUE, it removes NA from the vector or a data frame.

Return Value

It returns the maximum value of a vector or data frame.

Example 1: Finding the maximum value of a vector

Finding the maximum value of a vector

rv <- c(19, 21, -20, -46, 29)

cat("The maximum value of thev vector is:", max(rv))

Output

The maximum value of thev vector is: 29

You can see from the vector that mathematically, the maximum value is 29, and we get the same output.

Example 2: Ignoring NA values

If you add the NA value as missing data to the vector, it will return the NA value as a maximum value because it is not what the NA value is.

Use the max() function to a Vector containing NA values

rv <- c(19, 21, -20, NA, 29)

cat("The maximum value of thev vector is:", max(rv))

Output

The maximum value of thev vector is: NA

But don’t worry, and there is an easy solution! Just specify the option na.rm = TRUE within the max() function.

rv <- c(19, 21, -20, NA, 29)

cat("The maximum value of thev vector is:", max(rv, na.rm = TRUE))

Output

The maximum value of thev vector is: 29

Example 3: Using max() function on data frame

Using max() function on data frame

df <- data.frame(
  "col1" = c(21, 19, 11),
  "col2" = c(18, 46, 10),
  "col3" = c(5, 15, 25)
)

max(df)

Output

[1] 46

Example 4: Finding the maximum value between two columns

Finding the maximum value between two columns

df <- data.frame(
  "col1" = c(21, 19, 11),
  "col2" = c(18, 46, 10),
  "col3" = c(5, 15, 25)
)

max(c(df$col1, df$col3))

Output

[1] 25

Example 5: Finding the Maximum of the row

Figure of Finding the Maximum of the row using the max() Function

df <- data.frame(
  "col1" = c(21, 19, 11),
  "col2" = c(18, 46, 10),
  "col3" = c(5, 15, 25)
)

max(df[2, ])

Output

[1] 46

Example 6: Finding a global max value of a specific column of a dataset

data(ChickWeight)
val <- max(ChickWeight$weight)
cat("The maximum value of weight column is:", val)

Output

The maximum value of weight column is: 373

That means the maximum weight of the ChickWeight dataset is 373.

Example 7: Finding the maximum global value of the dataset

data(mtcars)
max(mtcars)

Output

[1] 472

That’s it.

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