This is an S3 Method to return a copy of an object with modified subsets.
Use sb_mod(x, ...) if x is an atomic object; this returns a full copy.
Use sb2_mod(x, ...) if x is a recursive object
(i.e. list or data.frame-like);
this returns a partial copy.
For modifying subsets using R's default copy-on-modification semantics, see idx.
Usage
sb_mod(x, ...)
# S3 method for default
sb_mod(
x,
i = NULL,
inv = FALSE,
...,
rp,
tf,
chkdup = getOption("squarebrackets.chkdup", FALSE)
)
# S3 method for array
sb_mod(
x,
sub = NULL,
dims = 1:ndims(x),
i = NULL,
inv = FALSE,
...,
rp,
tf,
chkdup = getOption("squarebrackets.chkdup", FALSE)
)
sb2_mod(x, ...)
# S3 method for default
sb2_mod(
x,
i = NULL,
inv = FALSE,
...,
rp,
tf,
chkdup = getOption("squarebrackets.chkdup", FALSE),
.lapply = lapply
)
# S3 method for array
sb2_mod(
x,
sub = NULL,
dims = 1:ndims(x),
i = NULL,
inv = FALSE,
...,
rp,
tf,
chkdup = getOption("squarebrackets.chkdup", FALSE),
.lapply = lapply
)
# S3 method for data.frame
sb2_mod(
x,
row = NULL,
col = NULL,
filter = NULL,
vars = NULL,
inv = FALSE,
...,
rp,
tf,
chkdup = getOption("squarebrackets.chkdup", FALSE),
.lapply = lapply
)Arguments
- x
- ...
- i, row, col, sub, dims, filter, vars, inv
See squarebrackets_indx_args.
An empty index selection returns the original object unchanged.- rp, tf, .lapply
- chkdup
![[for performance: set to FALSE]](figures/for_performance-set_to_FALSE-red.svg)
Details
Transform or Replace
Specifying argument tf will transform the subset.
Specifying rp will replace the subset.
One cannot specify both tf and rp. It's either one set or the other.
Examples
# atomic objects ====
obj <- matrix(1:16, ncol = 4)
colnames(obj) <- c("a", "b", "c", "a")
print(obj)
#> a b c a
#> [1,] 1 5 9 13
#> [2,] 2 6 10 14
#> [3,] 3 7 11 15
#> [4,] 4 8 12 16
rp <- -1:-9
sb_mod(obj, 1:3, 1:ndims(obj), rp = rp)
#> a b c a
#> [1,] -1 -4 -7 13
#> [2,] -2 -5 -8 14
#> [3,] -3 -6 -9 15
#> [4,] 4 8 12 16
# above is equivalent to obj[1:3, 1:3] <- -1:-9; obj
sb_mod(obj, i = \(x)x<=5, rp = -1:-5)
#> a b c a
#> [1,] -1 -5 9 13
#> [2,] -2 6 10 14
#> [3,] -3 7 11 15
#> [4,] -4 8 12 16
# above is equivalent to obj[obj <= 5] <- -1:-5; obj
sb_mod(obj, "a", 2L, rp = -1:-8)
#> a b c a
#> [1,] -1 5 9 -5
#> [2,] -2 6 10 -6
#> [3,] -3 7 11 -7
#> [4,] -4 8 12 -8
# above is equivalent to obj[, which(colnames(obj) %in% "a")] <- -1:-8; obj
sb_mod(obj, 1:3, 1:ndims(obj),tf = \(x) -x)
#> a b c a
#> [1,] -1 -5 -9 13
#> [2,] -2 -6 -10 14
#> [3,] -3 -7 -11 15
#> [4,] 4 8 12 16
# above is equivalent to obj[1:3, 1:3] <- (-1 * obj[1:3, 1:3]); obj
sb_mod(obj, i = \(x)x<=5, tf = \(x) -x)
#> a b c a
#> [1,] -1 -5 9 13
#> [2,] -2 6 10 14
#> [3,] -3 7 11 15
#> [4,] -4 8 12 16
# above is equivalent to obj[obj <= 5] <- (-1 * obj[obj <= 5]); obj
obj <- array(1:64, c(4,4,3))
print(obj)
#> , , 1
#>
#> [,1] [,2] [,3] [,4]
#> [1,] 1 5 9 13
#> [2,] 2 6 10 14
#> [3,] 3 7 11 15
#> [4,] 4 8 12 16
#>
#> , , 2
#>
#> [,1] [,2] [,3] [,4]
#> [1,] 17 21 25 29
#> [2,] 18 22 26 30
#> [3,] 19 23 27 31
#> [4,] 20 24 28 32
#>
#> , , 3
#>
#> [,1] [,2] [,3] [,4]
#> [1,] 33 37 41 45
#> [2,] 34 38 42 46
#> [3,] 35 39 43 47
#> [4,] 36 40 44 48
#>
sb_mod(obj, n(1:3, 1:2), c(1,3), rp = -1:-24)
#> , , 1
#>
#> [,1] [,2] [,3] [,4]
#> [1,] -1 -4 -7 -10
#> [2,] -2 -5 -8 -11
#> [3,] -3 -6 -9 -12
#> [4,] 4 8 12 16
#>
#> , , 2
#>
#> [,1] [,2] [,3] [,4]
#> [1,] -13 -16 -19 -22
#> [2,] -14 -17 -20 -23
#> [3,] -15 -18 -21 -24
#> [4,] 20 24 28 32
#>
#> , , 3
#>
#> [,1] [,2] [,3] [,4]
#> [1,] 33 37 41 45
#> [2,] 34 38 42 46
#> [3,] 35 39 43 47
#> [4,] 36 40 44 48
#>
# above is equivalent to obj[1:3, , 1:2] <- -1:-24
sb_mod(obj, i = \(x)x <= 5, rp = -1:-5)
#> , , 1
#>
#> [,1] [,2] [,3] [,4]
#> [1,] -1 -5 9 13
#> [2,] -2 6 10 14
#> [3,] -3 7 11 15
#> [4,] -4 8 12 16
#>
#> , , 2
#>
#> [,1] [,2] [,3] [,4]
#> [1,] 17 21 25 29
#> [2,] 18 22 26 30
#> [3,] 19 23 27 31
#> [4,] 20 24 28 32
#>
#> , , 3
#>
#> [,1] [,2] [,3] [,4]
#> [1,] 33 37 41 45
#> [2,] 34 38 42 46
#> [3,] 35 39 43 47
#> [4,] 36 40 44 48
#>
# above is equivalent to obj[obj <= 5] <- -1:-5
#############################################################################
# lists ====
obj <- list(a = 1:10, b = letters[1:11], c = 11:20)
print(obj)
#> $a
#> [1] 1 2 3 4 5 6 7 8 9 10
#>
#> $b
#> [1] "a" "b" "c" "d" "e" "f" "g" "h" "i" "j" "k"
#>
#> $c
#> [1] 11 12 13 14 15 16 17 18 19 20
#>
sb2_mod(obj, "a", rp = list(1L))
#> $a
#> [1] 1
#>
#> $b
#> [1] "a" "b" "c" "d" "e" "f" "g" "h" "i" "j" "k"
#>
#> $c
#> [1] 11 12 13 14 15 16 17 18 19 20
#>
# above is equivalent to obj[["a"]] <- 1L; obj
sb2_mod(obj, is.numeric, rp = list(-1:-10, -11:-20))
#> $a
#> [1] -1 -2 -3 -4 -5 -6 -7 -8 -9 -10
#>
#> $b
#> [1] "a" "b" "c" "d" "e" "f" "g" "h" "i" "j" "k"
#>
#> $c
#> [1] -11 -12 -13 -14 -15 -16 -17 -18 -19 -20
#>
# above is equivalent to obj[which(sapply(obj, is.numeric))] <- list(-1:-10, -11:-20); obj
obj <- rbind(
lapply(1:4, \(x)sample(c(TRUE, FALSE, NA))),
lapply(1:4, \(x)sample(1:10)),
lapply(1:4, \(x)rnorm(10)),
lapply(1:4, \(x)sample(letters))
)
colnames(obj) <- c("a", "b", "c", "a")
print(obj)
#> a b c a
#> [1,] logical,3 logical,3 logical,3 logical,3
#> [2,] integer,10 integer,10 integer,10 integer,10
#> [3,] numeric,10 numeric,10 numeric,10 numeric,10
#> [4,] character,26 character,26 character,26 character,26
sb2_mod(obj, 1:3, 1:ndims(obj),rp = n(-1))
#> a b c a
#> [1,] -1 -1 -1 logical,3
#> [2,] -1 -1 -1 integer,10
#> [3,] -1 -1 -1 numeric,10
#> [4,] character,26 character,26 character,26 character,26
# above is equivalent to obj[1:3, 1:3] <- list(-1)
sb2_mod(obj, i = is.numeric, rp = n(-1))
#> a b c a
#> [1,] logical,3 logical,3 logical,3 logical,3
#> [2,] -1 -1 -1 -1
#> [3,] -1 -1 -1 -1
#> [4,] character,26 character,26 character,26 character,26
# above is equivalent to obj[sapply(obj, is.numeric)] <- list(-1)
sb2_mod(obj, "a", 2L, rp = n(-1))
#> a b c a
#> [1,] -1 logical,3 logical,3 -1
#> [2,] -1 integer,10 integer,10 -1
#> [3,] -1 numeric,10 numeric,10 -1
#> [4,] -1 character,26 character,26 -1
# above is equivalent to
# obj[, lapply(c("a", "a"), \(i) which(colnames(obj) == i)) |> unlist()] <- list(-1)
obj <- array(as.list(1:64), c(4,4,3))
print(obj)
#> , , 1
#>
#> [,1] [,2] [,3] [,4]
#> [1,] 1 5 9 13
#> [2,] 2 6 10 14
#> [3,] 3 7 11 15
#> [4,] 4 8 12 16
#>
#> , , 2
#>
#> [,1] [,2] [,3] [,4]
#> [1,] 17 21 25 29
#> [2,] 18 22 26 30
#> [3,] 19 23 27 31
#> [4,] 20 24 28 32
#>
#> , , 3
#>
#> [,1] [,2] [,3] [,4]
#> [1,] 33 37 41 45
#> [2,] 34 38 42 46
#> [3,] 35 39 43 47
#> [4,] 36 40 44 48
#>
sb2_mod(obj, n(1:3, 1:2), c(1,3), rp = as.list(-1:-24))
#> , , 1
#>
#> [,1] [,2] [,3] [,4]
#> [1,] -1 -4 -7 -10
#> [2,] -2 -5 -8 -11
#> [3,] -3 -6 -9 -12
#> [4,] 4 8 12 16
#>
#> , , 2
#>
#> [,1] [,2] [,3] [,4]
#> [1,] -13 -16 -19 -22
#> [2,] -14 -17 -20 -23
#> [3,] -15 -18 -21 -24
#> [4,] 20 24 28 32
#>
#> , , 3
#>
#> [,1] [,2] [,3] [,4]
#> [1,] 33 37 41 45
#> [2,] 34 38 42 46
#> [3,] 35 39 43 47
#> [4,] 36 40 44 48
#>
# above is equivalent to obj[1:3, , 1:2] <- as.list(-1:-24)
sb2_mod(obj, i = \(x) x <= 5, rp = as.list(-1:-5))
#> , , 1
#>
#> [,1] [,2] [,3] [,4]
#> [1,] -1 -5 9 13
#> [2,] -2 6 10 14
#> [3,] -3 7 11 15
#> [4,] -4 8 12 16
#>
#> , , 2
#>
#> [,1] [,2] [,3] [,4]
#> [1,] 17 21 25 29
#> [2,] 18 22 26 30
#> [3,] 19 23 27 31
#> [4,] 20 24 28 32
#>
#> , , 3
#>
#> [,1] [,2] [,3] [,4]
#> [1,] 33 37 41 45
#> [2,] 34 38 42 46
#> [3,] 35 39 43 47
#> [4,] 36 40 44 48
#>
# above is equivalent to obj[sapply(onj, \(x) x <= 5)] <- as.list(-1:-5)
#############################################################################
# data.frame-like objects - whole columns ====
obj <- data.frame(a = 1:10, b = letters[1:10], c = 11:20, d = factor(letters[1:10]))
str(obj) # notice that columns "a" and "c" are INTEGER (`int`)
#> 'data.frame': 10 obs. of 4 variables:
#> $ a: int 1 2 3 4 5 6 7 8 9 10
#> $ b: chr "a" "b" "c" "d" ...
#> $ c: int 11 12 13 14 15 16 17 18 19 20
#> $ d: Factor w/ 10 levels "a","b","c","d",..: 1 2 3 4 5 6 7 8 9 10
sb2_mod(
obj, vars = is.numeric,
tf = sqrt
)
#> a b c d
#> 1 1.000000 a 3.316625 a
#> 2 1.414214 b 3.464102 b
#> 3 1.732051 c 3.605551 c
#> 4 2.000000 d 3.741657 d
#> 5 2.236068 e 3.872983 e
#> 6 2.449490 f 4.000000 f
#> 7 2.645751 g 4.123106 g
#> 8 2.828427 h 4.242641 h
#> 9 3.000000 i 4.358899 i
#> 10 3.162278 j 4.472136 j
#############################################################################
# data.frame-like objects - partial columns ====
obj <- data.frame(a = 1:10, b = letters[1:10], c = 11:20, d = factor(letters[1:10]))
str(obj) # notice that columns "a" and "c" are INTEGER (`int`)
#> 'data.frame': 10 obs. of 4 variables:
#> $ a: int 1 2 3 4 5 6 7 8 9 10
#> $ b: chr "a" "b" "c" "d" ...
#> $ c: int 11 12 13 14 15 16 17 18 19 20
#> $ d: Factor w/ 10 levels "a","b","c","d",..: 1 2 3 4 5 6 7 8 9 10
sb2_mod(
obj, filter = ~ (a >= 2) & (c <= 17), vars = is.numeric,
tf = sqrt
)
#> a b c d
#> 1 1.000000 a 11.000000 a
#> 2 1.414214 b 3.464102 b
#> 3 1.732051 c 3.605551 c
#> 4 2.000000 d 3.741657 d
#> 5 2.236068 e 3.872983 e
#> 6 2.449490 f 4.000000 f
#> 7 2.645751 g 4.123106 g
#> 8 8.000000 h 18.000000 h
#> 9 9.000000 i 19.000000 i
#> 10 10.000000 j 20.000000 j
sb2_mod(
obj, filter = ~ (a >= 2) & (c <= 17), vars = is.numeric,
tf = sqrt
)
#> a b c d
#> 1 1.000000 a 11.000000 a
#> 2 1.414214 b 3.464102 b
#> 3 1.732051 c 3.605551 c
#> 4 2.000000 d 3.741657 d
#> 5 2.236068 e 3.872983 e
#> 6 2.449490 f 4.000000 f
#> 7 2.645751 g 4.123106 g
#> 8 8.000000 h 18.000000 h
#> 9 9.000000 i 19.000000 i
#> 10 10.000000 j 20.000000 j
sb2_mod(
obj, filter = ~ (a >= 2) & (c <= 17), vars = is.numeric,
tf = sqrt
)
#> a b c d
#> 1 1.000000 a 11.000000 a
#> 2 1.414214 b 3.464102 b
#> 3 1.732051 c 3.605551 c
#> 4 2.000000 d 3.741657 d
#> 5 2.236068 e 3.872983 e
#> 6 2.449490 f 4.000000 f
#> 7 2.645751 g 4.123106 g
#> 8 8.000000 h 18.000000 h
#> 9 9.000000 i 19.000000 i
#> 10 10.000000 j 20.000000 j