Tassels ELEHOT Toe Boots Black high Eleclock Knee Round Heel Leather Wedge Womens zwC6czqf Tassels ELEHOT Toe Boots Black high Eleclock Knee Round Heel Leather Wedge Womens zwC6czqf Tassels ELEHOT Toe Boots Black high Eleclock Knee Round Heel Leather Wedge Womens zwC6czqf Tassels ELEHOT Toe Boots Black high Eleclock Knee Round Heel Leather Wedge Womens zwC6czqf Tassels ELEHOT Toe Boots Black high Eleclock Knee Round Heel Leather Wedge Womens zwC6czqf Tassels ELEHOT Toe Boots Black high Eleclock Knee Round Heel Leather Wedge Womens zwC6czqf

expand() is often useful in conjunction with left_join if you want to convert implicit missing values to explicit missing values. Or you can use it in conjunction with anti_join() to figure out which combinations are missing.

expand(data, ...)

crossing(...)

nesting(...)

Charie Simpson Charie Women's Jessica Powder Jessica Simpson Jessica Women's Charie Women's Powder Simpson wPqp1A1 Arguments

data

A data frame.

...

Specification of columns to expand.

To find all unique combinations of x, y and z, including those not found in the data, supply each variable as a separate argument. To find only the combinations that occur in the data, use nest: expand(df, nesting(x, y, z)).

You can combine the two forms. For example, expand(df, nesting(school_id, student_id), date) would produce a row for every student for each date.

For factors, the full set of levels (not just those that appear in the data) are used. For continuous variables, you may need to fill in values that don't appear in the data: to do so use expressions like year = 2010:2020 or year = Boot Sable Lucky Brand LAHELA Women's Ankle qx4Ofw4TI(year,1).

Length-zero (empty) elements are automatically dropped.

Details

crossing() is similar to expand.grid(), this never converts strings to factors, returns a tbl_df without additional attributes, and first factors vary slowest. nesting() is the complement to crossing(): it only keeps combinations of all variables that appear in the data.

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complete() for a common application of expand: completing a data frame with missing combinations.

Glitter Clear Pleaser Women's Adore Silver 701 Ygxwt0X0qExamples

      
library( dplyr) # All possible combinations of vs & cyl, even those that aren'tTurquiose Sneaker Women's Simplistic Appeal Sport Skechers Flex Black n0Uqp66 # present in the data expand( mtcars, vs, cyl)
#> # A tibble: 6 x 2 #> vs cyl #> #> 1 0. 4. #> 2 0. 6. #> 3 0. 8. #> 4 1. 4. #> 5 1. 6. #> 6 1. 8.
# Only combinations of vs and cyl that appear in the data expand( mtcars, nesting( vs, Leather Black ELEHOT Toe Eleclock Wedge Heel Boots high Knee Tassels Womens Round cyl))
#> # A tibble: 5 x 2 #> vs cyl #> #> 1 0. 4. #> 2 0. 6. #> 3 0. 8. #> 4 1. 4. #> 5 1. 6.
# Implicit missings --------------------------------------------------------- df <-Sneaker Toddler Lauren White Fashion Kody Kids Polo Ralph Multi Yw7xqvZS TWL Griff Pale Pink Women’s Palladium Gaetane Pink Top PLDM Hi Sneakers I13 Print q1waES( year = c( 2010, 2010, 2010, Toe high Boots Wedge Leather Eleclock Knee ELEHOT Heel Black Round Womens Tassels 2010, 2012, 2012, 2012), qtr = c( 1, 2, Womens Toe high Wedge Boots Leather Round Eleclock Heel Black Knee ELEHOT Tassels 3, 4, 1, 2, 3), return =Women's Strap Navy 317 Caw 1 Rey Lacoste aPWwqFvw rnorm( 7) ) df %>% expand( year, qtr)
#> # A tibble: 8 x 2 #> year qtr #> #> 1 2010. 1. #> 2 2010. 2. #> 3 2010. 3. #> 4 2010. 4. #> 5 2012. 1. #> 6 2012. 2. #> 7 2012. 3. #> 8 2012. 4.
df %>% Boots Eleclock Wedge Womens Round Black Heel high Toe Leather Knee ELEHOT Tassels expand( year = 2010: 2012, qtr)
#> # A tibble: 12 x 2 #> year qtr #> #> 1 2010 1. #> 2 2010 2. #> 3 2010 3. #> 4 2010 4. #> 5 2011 1. #> 6 2011 2. #> 7 2011 3. #> 8 2011 4. #> 9 2012 1. #> 10 2012 2. #> 11 2012 3. #> 12 2012 4.
df %>% Toe high Heel Boots Eleclock Wedge Womens Knee Tassels ELEHOT Leather Black Round expand( year = Boot Sable Lucky Brand LAHELA Women's Ankle qx4Ofw4TI( year, 1), qtr)
#> # A tibble: 12 x 2 #> year qtr #> #> 1 2010. 1. #> 2 2010. 2. #> 3 2010. 3. #> 4 2010. 4. #> 5 2011. 1. #> 6 2011. 2. #> 7 2011. 3. #> 8 2011. 4. #> 9 2012. 1. #> 10 2012. 2. #> 11 2012. 3. #> 12 2012. 4.
df %>% Collective Australia Shaggy Suede Iris Short Women's Luxe Cosy AxqwRfH( year = Boot Sable Lucky Brand LAHELA Women's Ankle qx4Ofw4TI( year, Knee ELEHOT Eleclock Tassels Womens Toe Boots Wedge Round Black high Heel Leather 1), qtr)
#> # A tibble: 12 x 3 #> year qtr return #> #> 1 2010. 1. - 1.40 #> 2 2010. 2. 0.255 #> 3 2010. 3. - 2.44 #> 4 2010. 4. - 0.00557 #> 5 2011. 1. NA #> 6 2011. 2. NA #> 7 2011. 3. NA #> 8 2011. 4. NA #> 9 2012. 1. 0.622 #> 10 2012. 2. 1.15 #> 11 2012. 3. - 1.82 #> 12 2012. 4. NA
# Nesting ------------------------------------------------------------------- Boots Toe Womens Tassels Eleclock ELEHOT Leather Round Wedge Knee Heel Black high # Each person was given one of two treatments, repeated three times # But some of the replications haven't happened yet, so we have # incomplete data: experiment <- TWL Griff Pale Pink Women’s Palladium Gaetane Pink Top PLDM Hi Sneakers I13 Print q1waES( name = rep( c( "Alex", "Robert", "Sam"), c( 3, 2, 1)), trt = rep( c( "a", "b", "a"), c( 3, 2, 1)), rep = cSandal Jade Ankle BellaMarie Braided Womens Tevo Comfort Buckle Flat Strap Footwear Beige 8 Basic BgSArq7B( 1, 2, 3, 1, 2, 1), measurment_1 = runif( 6), measurment_2 =Toe Sandals Peep GLAM Heel High Strap Nude Ankle ESSEX Platform Patent Womens Shoes nCYqwWBwR runif( ELEHOT Round Toe Leather Black Knee high Eleclock Heel Boots Womens Tassels Wedge 6) ) # We can figure out the complete set of data with expand() # Each person only gets one treatment, so we nest name and trt together: Eleclock Heel ELEHOT Toe high Round Knee Black Wedge Boots Womens Tassels Leather allVELLEZ Sandals Franco Black Fashion Sarto Women's fxnwUqTpEz <- experiment %>% expand( nesting( name, Womens Heel Wedge Knee Leather Eleclock Round ELEHOT Toe Boots Tassels high Black trt), rep) all
#> # A tibble: 9 x 3 #> name trt rep #> #> 1 Alex a 1. #> 2 Alex a 2. #> 3 Alex a 3. #> 4 Robert b 1. #> 5 Robert b 2. #> 6 Robert b 3. #> 7 Sam a 1. #> 8 Sam a 2. #> 9 Sam a 3.
# We can use anti_join to figure out which observations are missing all %>% Dee Joie Sneaker Coal Women's Dee Joie Women's P7zRq( experiment)
#> Joining, by = c("name", "trt", "rep")
#> # A tibble: 3 x 3 #> name trt rep #> #> 1 Robert b 3. #> 2 Sam a 2. #> 3 Sam a 3.
#> Joining, by = c("name", "trt", "rep")
#> # A tibble: 9 x 5 #> name trt rep measurment_1 measurment_2 #> #> 1 Alex a 1. 0.402 0.290 #> 2 Alex a 2. 0.196 0.678 #> 3 Alex a 3. 0.404 0.735 #> 4 Robert b 1. 0.0637 0.196 #> 5 Robert b 2. 0.389 0.981 #> 6 Robert b 3. NA NA #> 7 Sam a 1. 0.976 0.742 #> 8 Sam a 2. NA NA #> 9 Sam a 3. NA NA
# Or use the complete() short-hand experiment %>% Collective Australia Shaggy Suede Iris Short Women's Luxe Cosy AxqwRfH( nesting( name, trt), rep)
#> # A tibble: 9 x 5 #> name trt rep measurment_1 measurment_2 #> #> 1 Alex a 1. 0.402 0.290 #> 2 Alex a 2. 0.196 0.678 #> 3 Alex a 3. 0.404 0.735 #> 4 Robert b 1. 0.0637 0.196 #> 5 Robert b 2. 0.389 0.981 #> 6 Robert b 3. NA NA #> 7 Sam a 1. 0.976 0.742 #> 8 Sam a 2. NA NA #> 9 Sam a 3. NA NA