utils table manipulation methods for zoomed_dm objects — head.zoomed_dm" />

Extract the first or last rows from a table. Use these methods without the '.zoomed_dm' suffix (see examples). The methods for regular dm objects extract the first or last tables.

# S3 method for zoomed_dm
head(x, n = 6L, ...)

# S3 method for zoomed_dm
tail(x, n = 6L, ...)

Arguments

x

object of class zoomed_dm

n

an integer vector of length up to dim(x) (or 1, for non-dimensioned objects). Values specify the indices to be selected in the corresponding dimension (or along the length) of the object. A positive value of n[i] includes the first/last n[i] indices in that dimension, while a negative value excludes the last/first abs(n[i]), including all remaining indices. NA or non-specified values (when length(n) < length(dim(x))) select all indices in that dimension. Must contain at least one non-missing value.

...

arguments to be passed to or from other methods.

Value

A zoomed_dm object.

Details

see manual for the corresponding functions in utils.

Examples

zoomed <- dm_nycflights13() %>% dm_zoom_to(flights) %>% head(4) zoomed
#> # Zoomed table: flights #> # A tibble: 4 x 19 #> year month day dep_time sched_dep_time dep_delay arr_time sched_arr_time #> <int> <int> <int> <int> <int> <dbl> <int> <int> #> 1 2013 1 10 3 2359 4 426 437 #> 2 2013 1 10 16 2359 17 447 444 #> 3 2013 1 10 450 500 -10 634 648 #> 4 2013 1 10 520 525 -5 813 820 #> # … with 11 more variables: arr_delay <dbl>, carrier <chr>, flight <int>, #> # tailnum <chr>, origin <chr>, dest <chr>, air_time <dbl>, distance <dbl>, #> # hour <dbl>, minute <dbl>, time_hour <dttm>
dm_insert_zoomed(zoomed, new_tbl_name = "head_flights")
#> ── Table source ──────────────────────────────────────────────────────────────── #> src: <environment: R_GlobalEnv> #> ── Metadata ──────────────────────────────────────────────────────────────────── #> Tables: `airlines`, `airports`, `flights`, `planes`, `weather`, `head_flights` #> Columns: 72 #> Primary keys: 3 #> Foreign keys: 6