In nanoarrow an 'array' refers to the struct ArrowArray definition
in the Arrow C data interface. At the R level, we attach a
schema such that functionally the nanoarrow_array
class can be used in a similar way as an arrow::Array. Note that in
nanoarrow an arrow::RecordBatch and a non-nullable arrow::StructArray
are represented identically.
Arguments
- x
An object to convert to a array
- ...
Passed to S3 methods
- schema
An optional schema used to enforce conversion to a particular type. Defaults to
infer_nanoarrow_schema().
Examples
(array <- as_nanoarrow_array(1:5))
#> <nanoarrow_array int32[5]>
#> $ length : int 5
#> $ null_count: int 0
#> $ offset : int 0
#> $ buffers :List of 2
#> ..$ :<nanoarrow_buffer validity<bool>[null] ``
#> ..$ :<nanoarrow_buffer data<int32>[5][20 b]> `1 2 3 4 5`
#> $ dictionary: NULL
#> $ children : list()
as.vector(array)
#> [1] 1 2 3 4 5
(array <- as_nanoarrow_array(data.frame(x = 1:5)))
#> <nanoarrow_array struct[5]>
#> $ length : int 5
#> $ null_count: int 0
#> $ offset : int 0
#> $ buffers :List of 1
#> ..$ :<nanoarrow_buffer validity<bool>[null] ``
#> $ children :List of 1
#> ..$ x:<nanoarrow_array int32[5]>
#> .. ..$ length : int 5
#> .. ..$ null_count: int 0
#> .. ..$ offset : int 0
#> .. ..$ buffers :List of 2
#> .. .. ..$ :<nanoarrow_buffer validity<bool>[null] ``
#> .. .. ..$ :<nanoarrow_buffer data<int32>[5][20 b]> `1 2 3 4 5`
#> .. ..$ dictionary: NULL
#> .. ..$ children : list()
#> $ dictionary: NULL
as.data.frame(array)
#> x
#> 1 1
#> 2 2
#> 3 3
#> 4 4
#> 5 5