dplyr: A grammar of data manipulation
Fixed edge case of slice_sample() when weight_by= is used and there
0 rows (#5729).
across() can again use columns in functions defined inline (#5734).
Using testthat 3rd edition.
Fixed bugs introduced in across() in previous version (#5765).
group_by() keeps attributes unrelated to the grouping (#5760).
The .cols= argument of if_any() and if_all() defaults to everything().
Improved performance for across(). This makes summarise(across()) and
mutate(across()) perform as well as the superseded colwise equivalents (#5697).
New functions if_any() and if_all() (#4770, #5713).
summarise() silently ignores NULL results (#5708).
Fixed a performance regression in mutate() when warnings occur once per
group (#5675). We no longer instrument warnings with debugging information
when mutate() is called within suppressWarnings().
summarise() no longer informs when the result is ungrouped (#5633).
group_by(.drop = FALSE) preserves ordered factors (@brianrice2, #5545).
count() and tally() are now generic.
Removed default fallbacks to lazyeval methods; this will yield better error messages when you call a dplyr function with the wrong input, and is part of our long term plan to remove the deprecated lazyeval interface.
inner_join() gains a keep parameter for consistency with the other
mutating joins (@patrickbarks, #5581).
Improved performance with many columns, with a dynamic data mask using active bindings and lazy chops (#5017).
mutate() and friends preserves row names in data frames once more (#5418).
group_by() uses the ungrouped data for the implicit mutate step (#5598).
You might have to define an ungroup() method for custom classes.
For example, see https://github.com/hadley/cubelyr/pull/3.
relocate() can rename columns it relocates (#5569).
distinct() and group_by() have better error messages when the mutate step fails (#5060).
Clarify that between() is not vectorised (#5493).
Fixed across() issue where data frame columns would could not be referred to
with all_of() in the nested case (mutate() within mutate()) (#5498).
across() handles data frames with 0 columns (#5523).
mutate() always keeps grouping variables, unconditional to .keep= (#5582).
dplyr now depends on R 3.3.0
Fixed across() issue where data frame columns would mask objects referred to
from all_of() (#5460).
bind_cols() gains a .name_repair argument, passed to vctrs::vec_cbind() (#5451)
summarise(.groups = "rowwise") makes a rowwise data frame even if the input data
is not grouped (#5422).
New function cur_data_all() similar to cur_data() but includes the grouping variables (#5342).
count() and tally() no longer automatically weights by column n if
present (#5298). dplyr 1.0.0 introduced this behaviour because of Hadley's
faulty memory. Historically tally() automatically weighted and count()
did not, but this behaviour was accidentally changed in 0.8.2 (#4408) so that
neither automatically weighted by n. Since 0.8.2 is almost a year old,
and the automatically weighting behaviour was a little confusing anyway,
we've removed it from both count() and tally().
Use of wt = n() is now deprecated; now just omit the wt argument.
coalesce() now supports data frames correctly (#5326).
cummean() no longer has off-by-one indexing problem (@cropgen, #5287).
The call stack is preserved on error. This makes it possible to recover()
into problematic code called from dplyr verbs (#5308).
bind_cols() no longer converts to a tibble, returns a data frame if the input is a data frame.
bind_rows(), *_join(), summarise() and mutate() use vctrs coercion
rules. There are two main user facing changes:
Combining factor and character vectors silently creates a character vector; previously it created a character vector with a warning.
Combining multiple factors creates a factor with combined levels; previously it created a character vector with a warning.
bind_rows() and other functions use vctrs name repair, see ?vctrs::vec_as_names.
all.equal.tbl_df() removed.
Data frames, tibbles and grouped data frames are no longer considered equal, even if the data is the same.
Equality checks for data frames no longer ignore row order or groupings.
expect_equal() uses all.equal() internally. When comparing data frames, tests that used to pass may now fail.
distinct() keeps the original column order.
distinct() on missing columns now raises an error, it has been a compatibility warning for a long time.
group_modify() puts the grouping variable to the front.
n() and row_number() can no longer be called directly when dplyr is not loaded,
and this now generates an error: dplyr::mutate(mtcars, x = n()).
Fix by prefixing with dplyr:: as in dplyr::mutate(mtcars, x = dplyr::n())
The old data format for grouped_df is no longer supported. This may affect you if you have serialized grouped data frames to disk, e.g. with saveRDS() or when using knitr caching.
lead() and lag() are stricter about their inputs.
Extending data frames requires that the extra class or classes are added first, not last. Having the exta class at the end causes some vctrs operations to fail with a mesage like:
Input must be a vector, not a `<data.frame/...>` object
right_join() no longer sorts the rows of the resulting tibble according to the order of the RHS by argument in tibble y.
The cur_ functions (cur_data(), cur_group(), cur_group_id(),
cur_group_rows()) provide a full set of options to you access information
about the "current" group in dplyr verbs. They are inspired by
data.table's .SD, .GRP, .BY, and .I.
The rows_ functions (rows_insert(), rows_update(), rows_upsert(), rows_patch(), rows_delete()) provide a new API to insert and delete rows from a second data frame or table. Support for updating mutable backends is planned (#4654).
mutate() and summarise() create multiple columns from a single expression
if you return a data frame (#2326).
select() and rename() use the latest version of the tidyselect interface.
Practically, this means that you can now combine selections using Boolean
logic (i.e. !, & and |), and use predicate functions with where()
(e.g. where(is.character)) to select variables by type (#4680). It also makes
it possible to use select() and rename() to repair data frames with
duplicated names (#4615) and prevents you from accidentally introducing
duplicate names (#4643). This also means that dplyr now re-exports any_of()
and all_of() (#5036).
slice() gains a new set of helpers:
slice_head() and slice_tail() select the first and last rows, like
head() and tail(), but return n rows per group.
slice_sample() randomly selects rows, taking over from sample_frac()
and sample_n().
slice_min() and slice_max() select the rows with the minimum or
maximum values of a variable, taking over from the confusing top_n().
summarise() can create summaries of greater than length 1 if you use a
summary function that returns multiple values.
summarise() gains a .groups= argument to control the grouping structure.
New relocate() verb makes it easy to move columns around within a data
frame (#4598).
New rename_with() is designed specifically for the purpose of renaming
selected columns with a function (#4771).
ungroup() can now selectively remove grouping variables (#3760).
pull() can now return named vectors by specifying an additional column name
(@ilarischeinin, #4102).
mutate() (for data frames only), gains experimental new arguments
.before and .after that allow you to control where the new columns are
placed (#2047).
mutate() (for data frames only), gains an experimental new argument
called .keep that allows you to control which variables are kept from
the input .data. .keep = "all" is the default; it keeps all variables.
.keep = "none" retains no input variables (except for grouping keys),
so behaves like transmute(). .keep = "unused" keeps only variables
not used to make new columns. .keep = "used" keeps only the input variables
used to create new columns; it's useful for double checking your work (#3721).
New, experimental, with_groups() makes it easy to temporarily group or
ungroup (#4711).
New function across() that can be used inside summarise(), mutate(),
and other verbs to apply a function (or a set of functions) to a selection of
columns. See vignette("colwise") for more details.
New function c_across() that can be used inside summarise() and mutate()
in row-wise data frames to easily (e.g.) compute a row-wise mean of all
numeric variables. See vignette("rowwise") for more details.
rowwise() is no longer questioning; we now understand that it's an
important tool when you don't have vectorised code. It now also allows you to
specify additional variables that should be preserved in the output when
summarising (#4723). The rowwise-ness is preserved by all operations;
you need to explicit drop it with as_tibble() or group_by().
New, experimental, nest_by(). It has the same interface as group_by(),
but returns a rowwise data frame of grouping keys, supplemental with a
list-column of data frames containing the rest of the data.
The implementation of all dplyr verbs have been changed to use primitives provided by the vctrs package. This makes it easier to add support for new types of vector, radically simplifies the implementation, and makes all dplyr verbs more consistent.
The place where you are mostly likely to be impacted by the coercion changes is when working with factors in joins or grouped mutates: now when combining factors with different levels, dplyr creates a new factor with the union of the levels. This matches base R more closely, and while perhaps strictly less correct, is much more convenient.
dplyr dropped its two heaviest dependencies: Rcpp and BH. This should make it considerably easier and faster to build from source.
The implementation of all verbs has been carefully thought through. This mostly makes implementation simpler but should hopefully increase consistency, and also makes it easier to adapt to dplyr to new data structures in the new future. Pragmatically, the biggest difference for most people will be that each verb documents its return value in terms of rows, columns, groups, and data frame attributes.
Row names are now preserved when working with data frames.
group_by() uses hashing from the vctrs package.
Grouped data frames now have names<-, [[<-, [<- and $<- methods that
re-generate the underlying grouping. Note that modifying grouping variables
in multiple steps (i.e. df$grp1 <- 1; df$grp2 <- 1) will be inefficient
since the data frame will be regrouped after each modification.
[.grouped_df now regroups to respect any grouping columns that have
been removed (#4708).
mutate() and summarise() can now modify grouping variables (#4709).
group_modify() works with additional arguments (@billdenney and @cderv, #4509)
group_by() does not create an arbitrary NA group when grouping by factors
with drop = TRUE (#4460).
options(lifecycle_verbosity = x) where
x is one of NULL, "quiet", "warning", and "error".id(), deprecated in dplyr 0.5.0, is now defunct.
failwith(), deprecated in dplyr 0.7.0, is now defunct.
tbl_cube() and nasa have been pulled out into a separate cubelyr package
(#4429).
rbind_all() and rbind_list() have been removed (@bjungbogati, #4430).
dr_dplyr() has been removed as it is no longer needed (#4433, @smwindecker).
Use of pkgconfig for setting na_matches argument to join functions is now
deprecated (#4914). This was rarely used, and I'm now confident that the
default is correct for R.
In add_count(), the drop argument has been deprecated because it didn't
actually affect the output.
add_rownames(): please use tibble::rownames_to_column() instead.
as.tbl() and tbl_df(): please use as_tibble() instead.
bench_tbls(), compare_tbls(), compare_tbls2(), eval_tbls() and
eval_tbls2() are now deprecated. That were only used in a handful of
packages, and we now believe that you're better off performing comparisons
more directly (#4675).
combine(): please use vctrs::vec_c() instead.
funs(): please use list() instead.
group_by(add = ): please use .add
instead.
group_by(.dots = )/group_by_prepare(.dots = ): please use !!!
instead (#4734).
The use of zero-arg group_indices() to retrieve the group id for the
"current" group is deprecated; instead use cur_group_id().
Passing arguments to group_keys() or group_indices() to change the
grouping has been deprecated, instead do grouping first yourself.
location() and changes(): please use lobstr::ref() instead.
progress_estimated() is soft deprecated; it's not the responsibility of
dplyr to provide progress bars (#4935).
src_local() has been deprecated; it was part of an approach to testing
dplyr backends that didn't pan out.
src_mysql(), src_postgres(), and src_sqlite() has been deprecated.
We've recommended against them for some time. Instead please use the approach
described at http://dbplyr.tidyverse.org/.
select_vars(), rename_vars(), select_var(), current_vars() are now
deprecated (@perezp44, #4432)
The scoped helpers (all functions ending in _if, _at, or _all) have
been superseded by across(). This dramatically reduces the API surface for
dplyr, while at the same providing providing a more flexible and less
error-prone interface (#4769).
rename_*() and select_*() have been superseded by rename_with().
do() is superseded in favour of summarise().
sample_n() and sample_frac() have been superseded by slice_sample().
See ?sample_n for details about why, and for examples converting from
old to new usage.
top_n() has been superseded byslice_min()/slice_max(). See ?top_n
for details about why, and how to convert old to new usage (#4494).
all_equal() is questioning; it solves a problem that no longer seems
important.rowwise() is no longer questioning.New vignette("base") which describes how dplyr verbs relate to the
base R equivalents (@sastoudt, #4755)
New vignette("grouping") gives more details about how dplyr verbs change
when applied to grouped data frames (#4779, @MikeKSmith).
vignette("programming") has been completely rewritten to reflect our
latest vocabulary, the most recent rlang features, and our current
recommendations. It should now be substantially easier to program with
dplyr.
dplyr now has a rudimentary, experimental, and stop-gap, extension mechanism
documented in ?dplyr_extending
dplyr no longer provides a all.equal.tbl_df() method. It never should have
done so in the first place because it owns neither the generic nor the class.
It also provided a problematic implementation because, by default, it
ignored the order of the rows and the columns which is usually important.
This is likely to cause new test failures in downstream packages; but on
the whole we believe those failures to either reflect unexpected behaviour
or tests that need to be strengthened (#2751).
coalesce() now uses vctrs recycling and common type coercion rules (#5186).
count() and add_count() do a better job of preserving input class
and attributes (#4086).
distinct() errors if you request it use variables that don't exist
(this was previously a warning) (#4656).
filter(), mutate() and summarise() get better error messages.
filter() handles data frame results when all columns are logical vectors
by reducing them with & (#4678). In particular this means across() can
be used in filter().
left_join(), right_join(), and full_join() gain a keep argument so
that you can optionally choose to keep both sets of join keys (#4589). This is
useful when you want to figure out which rows were missing from either side.
Join functions can now perform a cross-join by specifying by = character()
(#4206.)
groups() now returns list() for ungrouped data; previously it returned
NULL which was type-unstable (when there are groups it returns a list
of symbols).
The first argument of group_map(), group_modify() and group_walk()
has been changed to .data for consistency with other generics.
group_keys.rowwise_df() gives a 0 column data frame with n() rows.
group_map() is now a generic (#4576).
group_by(..., .add = TRUE) replaces group_by(..., add = TRUE),
with a deprecation message. The old argument name was a mistake because
it prevents you from creating a new grouping var called add and
it violates our naming conventions (#4137).
intersect(), union(), setdiff() and setequal() generics are now
imported from the generics package. This reduces a conflict with lubridate.
order_by() gives an informative hint if you accidentally call it instead
of arrange() #3357.
tally() and count() now message if the default output name (n), already
exists in the data frame. To quiet the message, you'll need to supply an
explicit name (#4284). You can override the default weighting to using a
constant by setting wt = 1.
starwars dataset now does a better job of separating biological sex from
gender identity. The previous gender column has been renamed to sex,
since it actually describes the individual's biological sex. A new gender
column encodes the actual gender identity using other information about
the Star Wars universe (@MeganBeckett, #4456).
src_tbls() accepts ... arguments (#4485, @ianmcook). This could be a
breaking change for some dplyr backend packages that implement src_tbls().
Better performance for extracting slices of factors and ordered factors (#4501).
rename_at() and rename_all() call the function with a simple character
vector, not a dplyr_sel_vars (#4459).
ntile() is now more consistent with database implementations if the buckets have irregular size (#4495).
Maintenance release for compatibility with R-devel.
top_frac(data, proportion) is a shorthand for top_n(data, proportion * n()) (#4017).Using quosures in colwise verbs is deprecated (#4330).
Updated distinct_if(), distinct_at() and distinct_all() to include .keep_all argument (@beansrowning, #4343).
rename_at() handles empty selection (#4324).
*_if() functions correctly handle columns with special names (#4380).
colwise functions support constants in formulas (#4374).
hybrid rank functions correctly handle NA (#4427).
first(), last() and nth() hybrid version handles factors (#4295).
top_n() quotes its n argument, n no longer needs to be constant for all groups (#4017).
tbl_vars() keeps information on grouping columns by returning a dplyr_sel_vars object (#4106).
group_split() always sets the ptype attribute, which make it more robust in the case where there
are 0 groups.
group_map() and group_modify() work in the 0 group edge case (#4421)
select.list() method added so that select() does not dispatch on lists (#4279).
view() is reexported from tibble (#4423).
group_by() puts NA groups last in character vectors (#4227).
arrange() handles integer64 objects (#4366).
summarise() correctly resolves summarised list columns (#4349).