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Reindex a data.frame

Source: R/expand.R
reindex.Rd

Reindexes a data.frame with a reference

Usage

reindex(
  x,
  index = NULL,
  new_index,
  expand = c("intersect", "both"),
  sort = FALSE
)

Arguments

x

A data.frame

index

The column name or number of an index to use; if NULL will assume the first column; a value of row.names will use row.names(x)

new_index

A column vector of the new index value

expand

Character switch to expand or keep only the values that intersect (none), all values in x or index, or retain all values found.

sort

Logical, if TRUE will sort the rows in output

Value

A data.frame with rows of index

Examples

iris1 <- head(iris, 5)
iris1$index <- 1:5
reindex(iris1, "index", seq(2, 8, 2))
#>   Sepal.Length Sepal.Width Petal.Length Petal.Width Species index
#> 2          4.9         3.0          1.4         0.2  setosa     2
#> 4          4.6         3.1          1.5         0.2  setosa     4
reindex(iris1, "index", seq(2, 8, 2), expand = "both")
#>   Sepal.Length Sepal.Width Petal.Length Petal.Width Species index
#> 1          5.1         3.5          1.4         0.2  setosa     1
#> 2          4.9         3.0          1.4         0.2  setosa     2
#> 3          4.7         3.2          1.3         0.2  setosa     3
#> 4          4.6         3.1          1.5         0.2  setosa     4
#> 5          5.0         3.6          1.4         0.2  setosa     5
#> 6           NA          NA           NA          NA    <NA>    NA
#> 8           NA          NA           NA          NA    <NA>    NA

# Using letters will show changes in rownames
iris1$index <- letters[1:5]
reindex(iris1, "index", letters[seq(2, 8, 2)])
#>   Sepal.Length Sepal.Width Petal.Length Petal.Width Species index
#> b           NA          NA           NA          NA    <NA>  <NA>
#> d           NA          NA           NA          NA    <NA>  <NA>
reindex(iris1, "index", seq(2, 8, 2))
#> [1] Sepal.Length Sepal.Width  Petal.Length Petal.Width  Species     
#> [6] index       
#> <0 rows> (or 0-length row.names)
reindex(iris1, "index", seq(2, 8, 2), expand = "both")
#>   Sepal.Length Sepal.Width Petal.Length Petal.Width Species index
#> a           NA          NA           NA          NA    <NA>  <NA>
#> b           NA          NA           NA          NA    <NA>  <NA>
#> c           NA          NA           NA          NA    <NA>  <NA>
#> d           NA          NA           NA          NA    <NA>  <NA>
#> e           NA          NA           NA          NA    <NA>  <NA>
#> 2          4.9         3.0          1.4         0.2  setosa     b
#> 4          4.6         3.1          1.5         0.2  setosa     d
#> 6           NA          NA           NA          NA    <NA>  <NA>
#> 8           NA          NA           NA          NA    <NA>  <NA>