The “select_if” Function in R
Package: dplyr
Purpose: To select columns in a data frame based on specified conditions applied to each column.
General Class: Data Manipulation
Required Argument(s):
data: The data frame to select columns from.
predicate: A function or formula specifying the conditions for column selection.
Notable Optional Arguments:
None.
Example (with Explanation):
# Load necessary packages
library(dplyr)
# Create a sample data frame
data <- data.frame(
ID = c(1, 2, 3),
value1 = c(10, 15, 20),
value2 = c(25, 30, 35),
category = c("A", "B", "A")
)
# Select columns where all values are numeric
selected_columns <- data %>%
select_if(is.numeric)
# Display the selected columns
print(selected_columns)In this example, the select_if function from the dplyr package is used to select columns from the sample data frame data where all values are numeric. The is.numeric predicate function is applied to each column, and only the numeric columns are retained in the selected_columns result.