I am experiencing strange behavior with the select dplyr function. It does not drop the variable from the data frame.
Here is the source data:
orig <- structure(list(park = structure(c(4L, 4L, 4L, 4L, 4L), .Label = c("miss", "piro", "sacn", "slbe"), class = "factor"), year = c(2006L, 2009L, 2006L, 2008L, 2009L), agent = structure(c(5L, 5L, 5L, 7L, 5L), .Label = c("agriculture", "beaver", "development", "flooding", "forest_pathogen", "harvest_00_20", "harvest_30_60", "harvest_70_90", "none"), class = "factor"), ha = c(4.32, 1.17, 3.51, 2.07, 9.18), loc_01 = structure(c(9L, 5L, 9L, 5L, 5L), .Label = c("miss", "non_miss", "non_piro", "non_sacn", "non_slbe", "none", "piro", "sacn", "slbe"), class = "factor"), loc_02 = structure(c(5L, 1L, 5L, 1L, 1L), .Label = c("none", "piro_core", "piro_ibz", "slbe_mainland", "slbe_southmanitou" ), class = "factor"), loc_03 = structure(c(1L, 1L, 1L, 1L, 1L), .Label = "none", class = "factor"), cross_valid = c(1L, 1L, 1L, 1L, 1L)), .Names = c("park", "year", "agent", "ha", "loc_01", "loc_02", "loc_03", "cross_valid"), row.names = c(NA, 5L), class = "data.frame")
Looks like:
> orig park year agent ha loc_01 loc_02 loc_03 cross_valid 1 slbe 2006 forest_pathogen 4.32 slbe slbe_southmanitou none 1 2 slbe 2009 forest_pathogen 1.17 non_slbe none none 1 3 slbe 2006 forest_pathogen 3.51 slbe slbe_southmanitou none 1 4 slbe 2008 harvest_30_60 2.07 non_slbe none none 1 5 slbe 2009 forest_pathogen 9.18 non_slbe none none 1 > str(orig) 'data.frame': 5 obs. of 8 variables: $ park : Factor w/ 4 levels "miss","piro",..: 4 4 4 4 4 $ year : int 2006 2009 2006 2008 2009 $ agent : Factor w/ 9 levels "agriculture",..: 5 5 5 7 5 $ ha : num 4.32 1.17 3.51 2.07 9.18 $ loc_01 : Factor w/ 9 levels "miss","non_miss",..: 9 5 9 5 5 $ loc_02 : Factor w/ 5 levels "none","piro_core",..: 5 1 5 1 1 $ loc_03 : Factor w/ 1 level "none": 1 1 1 1 1 $ cross_valid: int 1 1 1 1 1
Then I make a short summary ...
library (dplyr) summ <- orig %>% + group_by(park,cross_valid,agent) %>% + summarise(ha_dist=sum(ha)) summ Source: local data frame [2 x 4] Groups: park, cross_valid park cross_valid agent ha_dist 1 slbe 1 forest_pathogen 18.18 2 slbe 1 harvest_30_60 2.07 str(summ) Classes 'grouped_df', 'tbl_df', 'tbl' and 'data.frame': 2 obs. of 4 variables: $ park : Factor w/ 4 levels "miss","piro",..: 4 4 $ cross_valid: int 1 1 $ agent : Factor w/ 9 levels "agriculture",..: 5 7 $ ha_dist : num 18.18 2.07 - attr(*, "vars")=List of 2 ..$ : symbol park ..$ : symbol cross_valid - attr(*, "drop")= logi TRUE
Then I try to remove the 'cross_valid' ...
sel <- select (summ,-cross_valid) summ Source: local data frame [2 x 4] Groups: park, cross_valid park cross_valid agent ha_dist 1 slbe 1 forest_pathogen 18.18 2 slbe 1 harvest_30_60 2.07 str(summ) Classes 'grouped_df', 'tbl_df', 'tbl' and 'data.frame': 2 obs. of 4 variables: $ park : Factor w/ 4 levels "miss","piro",..: 4 4 $ cross_valid: int 1 1 $ agent : Factor w/ 9 levels "agriculture",..: 5 7 $ ha_dist : num 18.18 2.07 - attr(*, "vars")=List of 2 ..$ : symbol park ..$ : symbol cross_valid - attr(*, "drop")= logi TRUE - attr(*, "indices")=List of 1 ..$ : int 0 1 - attr(*, "group_sizes")= int 2 - attr(*, "biggest_group_size")= int 2 - attr(*, "labels")='data.frame': 1 obs. of 2 variables: ..$ park : Factor w/ 4 levels "miss","piro",..: 4 ..$ cross_valid: int 1 ..- attr(*, "vars")=List of 2 .. ..$ : symbol park .. ..$ : symbol cross_valid
And he will not fall summ$cross_valid
If I use the R base to remove cross_valid, it works ...
base.sel <- summ[-2] base.sel Source: local data frame [2 x 3] Groups: park agent ha_dist 1 slbe forest_pathogen 18.18 2 slbe harvest_30_60 2.07
I can reset orig$cross_valid with select ...
drop.orig <- select (orig,-cross_valid) drop.orig park year agent ha loc_01 loc_02 loc_03 1 slbe 2006 forest_pathogen 4.32 slbe slbe_southmanitou none 2 slbe 2009 forest_pathogen 1.17 non_slbe none none 3 slbe 2006 forest_pathogen 3.51 slbe slbe_southmanitou none 4 slbe 2008 harvest_30_60 2.07 non_slbe none none 5 slbe 2009 forest_pathogen 9.18 non_slbe none none
Since I can reset the variable with the base R, it doesn’t matter much, but I thought it might crash with dplyr. This is probably something with a variable structure, but I don't know what it will be.
Thanks..
-cherrytree