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Selects rows from data frame basing on the evaluation of the second argument
Pull(df, ...)Data frame to select from
Arguments to with(df, ...)
Data frame
If the first argument is not a data frame, function will stop with an error.
Pull() is similar to subset() (but is much simpler and allows non-logical values) and to dplyr::filter() function.
Please avoid using Pull() in non-ineractive mode.
# NOT RUN {
`[`(trees, 3, 1) # ... so square bracket is a command
## arguments of `[` are independent; this is why square bracket does not "catch" the context:
trees[trees$Girth < 11 & trees$Height == 65, ] # boring and long
trees[trees$Girth < 11 & sample(0:1, nrow(trees), replace=TRUE), ] # yes, boring, long but flexible
trees[with(trees, Girth < 11 & Height == 65), ] # less boring but still long
## it would be nice to avoid typing "trees" twice:
Pull(trees, Girth < 11 & Height == 65) # shorter
Pull(trees, Girth < 11 & sample(0:1, nrow(trees), replace=TRUE)) # flexibility is still here
Pull(trees, Girth < 11 & sample(0:1, nrow(trees),
replace=TRUE))$Height # if you want also select columns
Pull(trees, grep(81, Height)) # select not only by TRUE/FALSE but also by row index
# }
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