dplyr Summarize

Introduction

The summarize() function creates summary statistics from data. It's essential for aggregations.

Basic Summaries

library(dplyr)

df <- tibble(
  category = c("A", "B", "A", "B", "A"),
  value = c(10, 20, 30, 40, 50)
)

# Single summary
summarize(df, total = sum(value))

# Multiple summaries
summarize(df,
          total = sum(value),
          mean = mean(value),
          count = n())

Common Functions

summarize(df,
          sum = sum(value),
          mean = mean(value),
          median = median(value),
          sd = sd(value),
          min = min(value),
          max = max(value),
          n = n())

Grouped Summaries

df %>%
  group_by(category) %>%
  summarize(
    total = sum(value),
    mean = mean(value),
    count = n()
  )

Summary

summarize() creates aggregated statistics. Combine with group_by() for grouped summaries.