pct_window_prototype.R

# Experiments with R aggregates and window functions
# See http://cran.r-project.org/web/packages/dplyr/vignettes/window-functions.html

library(dplyr)
data(iris)

iris_pct <- iris %>%
    mutate(length_pct = Petal.Length / sum(Petal.Length))

iris_pct2 <- iris %>%
    mutate(length_pct_all = Petal.Length / sum(Petal.Length)) %>%
    group_by(Species) %>%
    mutate(length_pct_species = Petal.Length / sum(Petal.Length))

iris_total_all <- iris_pct %>%
    summarise(total_pct_all = sum(length_pct))

iris_total_by_species <- iris_pct2 %>%
    group_by(Species) %>%
    summarise(total_pct_species = sum(length_pct_species))