Extract parts of bigdist

Extract parts of bigdist

bigdist_extract(x, i, j, k, product = "outer")

Arguments

x	Object of class 'bigdist'
i	(integer vector) row positions
j	(integer vector) column positions
k	(integer vector) positions
product	(string) One among: 'inner', 'outer'(default)

Value

A matrix or vector of distances when product is 'outer' and 'inner' respectively

Details

In k-mode, both i and j should be missing and k should not be missing. In ij-mode, k should be missing and both i and j are optional. If i or j are missing, they are interpreted as all values of i or j (similar to matrix or dataframe subsetting).

Examples

set.seed(1)
amat <- matrix(rnorm(1e3), ncol = 10)
td   <- tempdir()
temp <- bigdist(mat = amat, file = file.path(td, "temp_ex6"))
#> ----
#> Location: /tmp/RtmpNBdlQr/temp_ex6_100_float.bk
#> Size on disk: 0 GB
#> Computing distances ... 
#> Completed!
#> ----
bigdist_extract(temp, 1, 2)
#>          [,1]
#> [1,] 4.631341
bigdist_extract(temp, 1:2, 3:4)
#>          [,1]     [,2]
#> [1,] 3.976406 3.531089
#> [2,] 5.591309 4.661480
bigdist_extract(temp, 1:2, 3:4, product = "inner")
#> [1] 3.976406 4.661480
dim(bigdist_extract(temp, 1:2,))
#> [1]   2 100
dim(bigdist_extract(temp, , 3:4))
#> [1] 100   2