r - Count function error (wrong result size) -

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i having weird problem using count function introduced today. when type: 

a <- count(data, c("col1", "col2")

error popping up

error: wrong result size

earlier code working fine. appreciated.

e.g data <- matrix((1,2,1,2,1,3,1,3,2,3,2,4,2,3,2,5), nrow=8, ncol=2)

most default dplyr functions made use data.frame column names unquoted (non-standard evaluation). hadley builds in standard eval versions, well, have same name, underscore (_) @ end: in case, count_(). standard eval ones can use quoted values arranged yours above:

count_(mtcars, c('cyl', 'gear'))

really, standard-eval versions overkill unless need pass variable stores name, though. in case, normal non-standard eval version work neatly, , produce same thing, while saving typing few quotes:

count(mtcars, cyl, gear)

either way, get

source: local data frame [8 x 3] groups: cyl [?]      cyl  gear     n   (dbl) (dbl) (int) 1     4     3     1 2     4     4     8 3     4     5     2 4     6     3     2 5     6     4     4 6     6     5     1 7     8     3    12 8     8     5     2

for more detail, see above link, though goes way more specifics need now.


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