shipunov (version 1.4)

Rows: Select rows from data frame

Description

Selects rows from data frame basing on logical on the evaluation of the second argument

Usage

Rows(df, ...)

Arguments

df

Data frame to select from

...

Arguments to with(df, ...)

Value

Data frame

Details

If the first argument is not a data frame, function will stop with error.

Rows() is similar to dplyr::filter() function.

Please avoid using Rows() in non-ineractive mode.

Examples

# 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$Girth < 11 & sample(0:1, nrow(trees), replace=TRUE), ] # yes, boring, long but flexible
trees[with(trees, Girth < 11 & Height == 65), ] # less boring but still long
## it would be nice to avoid typing "trees" twice:
Rows(trees, Girth < 11 & Height == 65) # shorter
Rows(trees, Girth < 11 & sample(0:1, nrow(trees), replace=TRUE)) # flexibility is still here
Rows(trees, Girth < 11 & sample(0:1, nrow(trees),
 replace=TRUE))$Height # if you want also select columns
Rows(trees, grep(81, Height)) # select not only by TRUE/FALSE but also by row index
# }