qdapTools 1.3.1

Split Data Forms at Specified Locations

Usage

loc_split(x, locs, names = NULL, ...)


"loc_split"(x, locs, names = NULL, ...)


"loc_split"(x, locs, names = NULL, ...)


"loc_split"(x, locs, names = NULL, ...)


"loc_split"(x, locs, names = NULL, ...)


"loc_split"(x, locs, names = NULL, ...)


"loc_split"(x, locs, names = NULL, ...)


"loc_split"(x, locs, names = NULL, ...)

Arguments

x
A data form (list, vector, data.frame, matrix).
locs
A vector of integer locations to split at. If locs contains the index 1, it will be silently dropped.
names
Optional vector of names to give to the list elements.
...
Ignored.

Value

Returns of list of data forms broken at the locs.

Description

Split data forms at specified integer locations.

Note

Two dimensional object will retain dimension (i.e., drop = FALSE is used).

Examples

## character
loc_split(LETTERS, c(4, 10, 16))



[[1]]
[1] "A" "B" "C"

[[2]]
[1] "D" "E" "F" "G" "H" "I"

[[3]]
[1] "J" "K" "L" "M" "N" "O"

[[4]]
 [1] "P" "Q" "R" "S" "T" "U" "V" "W" "X" "Y" "Z"




loc_split(LETTERS, c(4, 10, 16), c("dog", "cat", "chicken", "rabbit"))



$dog
[1] "A" "B" "C"

$cat
[1] "D" "E" "F" "G" "H" "I"

$chicken
[1] "J" "K" "L" "M" "N" "O"

$rabbit
 [1] "P" "Q" "R" "S" "T" "U" "V" "W" "X" "Y" "Z"





## numeric
loc_split(1:100, c(33, 66))



[[1]]
 [1]  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32

[[2]]
 [1] 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65

[[3]]
 [1]  66  67  68  69  70  71  72  73  74  75  76  77  78  79  80  81  82  83  84  85  86  87  88  89  90  91  92  93  94  95
[31]  96  97  98  99 100





## factor
(p_chng <- head(1 + cumsum(rle(as.character(CO2[["Plant"]]))[[1]]), -1))



 [1]  8 15 22 29 36 43 50 57 64 71 78



loc_split(CO2[["Plant"]], p_chng)



[[1]]
[1] Qn1 Qn1 Qn1 Qn1 Qn1 Qn1 Qn1
Levels: Qn1 < Qn2 < Qn3 < Qc1 < Qc3 < Qc2 < Mn3 < Mn2 < Mn1 < Mc2 < Mc3 < Mc1

[[2]]
[1] Qn2 Qn2 Qn2 Qn2 Qn2 Qn2 Qn2
Levels: Qn1 < Qn2 < Qn3 < Qc1 < Qc3 < Qc2 < Mn3 < Mn2 < Mn1 < Mc2 < Mc3 < Mc1

[[3]]
[1] Qn3 Qn3 Qn3 Qn3 Qn3 Qn3 Qn3
Levels: Qn1 < Qn2 < Qn3 < Qc1 < Qc3 < Qc2 < Mn3 < Mn2 < Mn1 < Mc2 < Mc3 < Mc1

[[4]]
[1] Qc1 Qc1 Qc1 Qc1 Qc1 Qc1 Qc1
Levels: Qn1 < Qn2 < Qn3 < Qc1 < Qc3 < Qc2 < Mn3 < Mn2 < Mn1 < Mc2 < Mc3 < Mc1

[[5]]
[1] Qc2 Qc2 Qc2 Qc2 Qc2 Qc2 Qc2
Levels: Qn1 < Qn2 < Qn3 < Qc1 < Qc3 < Qc2 < Mn3 < Mn2 < Mn1 < Mc2 < Mc3 < Mc1

[[6]]
[1] Qc3 Qc3 Qc3 Qc3 Qc3 Qc3 Qc3
Levels: Qn1 < Qn2 < Qn3 < Qc1 < Qc3 < Qc2 < Mn3 < Mn2 < Mn1 < Mc2 < Mc3 < Mc1

[[7]]
[1] Mn1 Mn1 Mn1 Mn1 Mn1 Mn1 Mn1
Levels: Qn1 < Qn2 < Qn3 < Qc1 < Qc3 < Qc2 < Mn3 < Mn2 < Mn1 < Mc2 < Mc3 < Mc1

[[8]]
[1] Mn2 Mn2 Mn2 Mn2 Mn2 Mn2 Mn2
Levels: Qn1 < Qn2 < Qn3 < Qc1 < Qc3 < Qc2 < Mn3 < Mn2 < Mn1 < Mc2 < Mc3 < Mc1

[[9]]
[1] Mn3 Mn3 Mn3 Mn3 Mn3 Mn3 Mn3
Levels: Qn1 < Qn2 < Qn3 < Qc1 < Qc3 < Qc2 < Mn3 < Mn2 < Mn1 < Mc2 < Mc3 < Mc1

[[10]]
[1] Mc1 Mc1 Mc1 Mc1 Mc1 Mc1 Mc1
Levels: Qn1 < Qn2 < Qn3 < Qc1 < Qc3 < Qc2 < Mn3 < Mn2 < Mn1 < Mc2 < Mc3 < Mc1

[[11]]
[1] Mc2 Mc2 Mc2 Mc2 Mc2 Mc2 Mc2
Levels: Qn1 < Qn2 < Qn3 < Qc1 < Qc3 < Qc2 < Mn3 < Mn2 < Mn1 < Mc2 < Mc3 < Mc1

[[12]]
[1] Mc3 Mc3 Mc3 Mc3 Mc3 Mc3 Mc3
Levels: Qn1 < Qn2 < Qn3 < Qc1 < Qc3 < Qc2 < Mn3 < Mn2 < Mn1 < Mc2 < Mc3 < Mc1





## list
loc_split(as.list(LETTERS), c(4, 10, 16))



[[1]]
[[1]][[1]]
[1] "A"

[[1]][[2]]
[1] "B"

[[1]][[3]]
[1] "C"


[[2]]
[[2]][[1]]
[1] "D"

[[2]][[2]]
[1] "E"

[[2]][[3]]
[1] "F"

[[2]][[4]]
[1] "G"

[[2]][[5]]
[1] "H"

[[2]][[6]]
[1] "I"


[[3]]
[[3]][[1]]
[1] "J"

[[3]][[2]]
[1] "K"

[[3]][[3]]
[1] "L"

[[3]][[4]]
[1] "M"

[[3]][[5]]
[1] "N"

[[3]][[6]]
[1] "O"


[[4]]
[[4]][[1]]
[1] "P"

[[4]][[2]]
[1] "Q"

[[4]][[3]]
[1] "R"

[[4]][[4]]
[1] "S"

[[4]][[5]]
[1] "T"

[[4]][[6]]
[1] "U"

[[4]][[7]]
[1] "V"

[[4]][[8]]
[1] "W"

[[4]][[9]]
[1] "X"

[[4]][[10]]
[1] "Y"

[[4]][[11]]
[1] "Z"






## data.frame
(vs_change <- head(1 + cumsum(rle(as.character(mtcars[["vs"]]))[[1]]), -1))



 [1]  3  5  6  7  8 12 18 22 26 27 28 29 32



loc_split(mtcars, vs_change)



[[1]]
              mpg cyl disp  hp drat    wt  qsec vs am gear carb
Mazda RX4      21   6  160 110  3.9 2.620 16.46  0  1    4    4
Mazda RX4 Wag  21   6  160 110  3.9 2.875 17.02  0  1    4    4

[[2]]
                mpg cyl disp  hp drat    wt  qsec vs am gear carb
Datsun 710     22.8   4  108  93 3.85 2.320 18.61  1  1    4    1
Hornet 4 Drive 21.4   6  258 110 3.08 3.215 19.44  1  0    3    1

[[3]]
                   mpg cyl disp  hp drat   wt  qsec vs am gear carb
Hornet Sportabout 18.7   8  360 175 3.15 3.44 17.02  0  0    3    2

[[4]]
         mpg cyl disp  hp drat   wt  qsec vs am gear carb
Valiant 18.1   6  225 105 2.76 3.46 20.22  1  0    3    1

[[5]]
            mpg cyl disp  hp drat   wt  qsec vs am gear carb
Duster 360 14.3   8  360 245 3.21 3.57 15.84  0  0    3    4

[[6]]
           mpg cyl  disp  hp drat   wt qsec vs am gear carb
Merc 240D 24.4   4 146.7  62 3.69 3.19 20.0  1  0    4    2
Merc 230  22.8   4 140.8  95 3.92 3.15 22.9  1  0    4    2
Merc 280  19.2   6 167.6 123 3.92 3.44 18.3  1  0    4    4
Merc 280C 17.8   6 167.6 123 3.92 3.44 18.9  1  0    4    4

[[7]]
                     mpg cyl  disp  hp drat    wt  qsec vs am gear carb
Merc 450SE          16.4   8 275.8 180 3.07 4.070 17.40  0  0    3    3
Merc 450SL          17.3   8 275.8 180 3.07 3.730 17.60  0  0    3    3
Merc 450SLC         15.2   8 275.8 180 3.07 3.780 18.00  0  0    3    3
Cadillac Fleetwood  10.4   8 472.0 205 2.93 5.250 17.98  0  0    3    4
Lincoln Continental 10.4   8 460.0 215 3.00 5.424 17.82  0  0    3    4
Chrysler Imperial   14.7   8 440.0 230 3.23 5.345 17.42  0  0    3    4

[[8]]
                mpg cyl  disp hp drat    wt  qsec vs am gear carb
Fiat 128       32.4   4  78.7 66 4.08 2.200 19.47  1  1    4    1
Honda Civic    30.4   4  75.7 52 4.93 1.615 18.52  1  1    4    2
Toyota Corolla 33.9   4  71.1 65 4.22 1.835 19.90  1  1    4    1
Toyota Corona  21.5   4 120.1 97 3.70 2.465 20.01  1  0    3    1

[[9]]
                  mpg cyl disp  hp drat    wt  qsec vs am gear carb
Dodge Challenger 15.5   8  318 150 2.76 3.520 16.87  0  0    3    2
AMC Javelin      15.2   8  304 150 3.15 3.435 17.30  0  0    3    2
Camaro Z28       13.3   8  350 245 3.73 3.840 15.41  0  0    3    4
Pontiac Firebird 19.2   8  400 175 3.08 3.845 17.05  0  0    3    2

[[10]]
           mpg cyl disp hp drat    wt qsec vs am gear carb
Fiat X1-9 27.3   4   79 66 4.08 1.935 18.9  1  1    4    1

[[11]]
              mpg cyl  disp hp drat   wt qsec vs am gear carb
Porsche 914-2  26   4 120.3 91 4.43 2.14 16.7  0  1    5    2

[[12]]
              mpg cyl disp  hp drat    wt qsec vs am gear carb
Lotus Europa 30.4   4 95.1 113 3.77 1.513 16.9  1  1    5    2

[[13]]
                mpg cyl disp  hp drat   wt qsec vs am gear carb
Ford Pantera L 15.8   8  351 264 4.22 3.17 14.5  0  1    5    4
Ferrari Dino   19.7   6  145 175 3.62 2.77 15.5  0  1    5    6
Maserati Bora  15.0   8  301 335 3.54 3.57 14.6  0  1    5    8

[[14]]
            mpg cyl disp  hp drat   wt qsec vs am gear carb
Volvo 142E 21.4   4  121 109 4.11 2.78 18.6  1  1    4    2





## matrix
(mat <- matrix(1:50, nrow=10))



      [,1] [,2] [,3] [,4] [,5]
 [1,]    1   11   21   31   41
 [2,]    2   12   22   32   42
 [3,]    3   13   23   33   43
 [4,]    4   14   24   34   44
 [5,]    5   15   25   35   45
 [6,]    6   16   26   36   46
 [7,]    7   17   27   37   47
 [8,]    8   18   28   38   48
 [9,]    9   19   29   39   49
[10,]   10   20   30   40   50



loc_split(mat, c(3, 6, 10))



[[1]]
     [,1] [,2] [,3] [,4] [,5]
[1,]    1   11   21   31   41
[2,]    2   12   22   32   42

[[2]]
     [,1] [,2] [,3] [,4] [,5]
[1,]    3   13   23   33   43
[2,]    4   14   24   34   44
[3,]    5   15   25   35   45

[[3]]
     [,1] [,2] [,3] [,4] [,5]
[1,]    6   16   26   36   46
[2,]    7   17   27   37   47
[3,]    8   18   28   38   48
[4,]    9   19   29   39   49

[[4]]
     [,1] [,2] [,3] [,4] [,5]
[1,]   10   20   30   40   50

See also

run_split, split_vector https://github.com/trinker/loc_split_example for practical usage.