`expand.grid()` for years and months

grid_dates.R

library(tidyverse)

# grid_ym ----
.years <- 2017:2018
.months <- 1:12

grid_ym <-
  crossing(
    year = .years, 
    month = .months
  ) %>% 
  as_tibble() %>% 
  mutate_all(as.integer)
        
# Or...
grid_ym  <-
  tibble(
    year = rep(.years, each = length(.months)),
    month = rep(.months, each = length(.years))
  ) %>% 
  mutate_all(as.integer)

# grid_ymd_hm ----
.date1 <- '2017-01-01'
.date2 <- '2018-12-31'
seq_days <- seq.Date(as.Date(.date1), as.Date(.date2), by = 'day')
grid_ymd <-
  seq_days %>% 
  tibble(date = .) %>% 
  mutate_at(
    vars(date), 
    list(
      year = lubridate::year,
      month = lubridate::month,
      day = lubridate::day
    )
  ) %>% 
  mutate_at(vars(-date), as.integer)
grid_ymd

grid_hm <- 
  crossing(
    hour = seq(1, 24, by = 1),
    minute = seq(5, 60, by = 5), 
    second = 0
  ) %>% 
  as_tibble() %>% 
  mutate_all(as.integer)
grid_hm

grid_ymd_hm <-
  grid_ymd %>% 
  mutate(dummy = 1) %>% 
  inner_join(grid_hm %>% mutate(dummy = 1)) %>% 
  arrange(date, hour, minute, second)
grid_ymd_hm