matter_vec-class {matter} | R Documentation |
The matter_vec
class implements on-disk vectors.
## Instance creation matter_vec(data, datamode = "double", paths = NULL, filemode = ifelse(all(file.exists(paths)), "rb", "rb+"), offset = 0, extent = length, length = 0L, names = NULL, ...) ## Additional methods documented below
data |
An optional data vector which will be initially written to the data on disk if provided. |
datamode |
A 'character' vector giving the storage mode of the data on disk. Allowable values are the C types ('char', 'uchar', short', 'ushort', 'int', 'uint', 'long', 'ulong', 'float') and their R equivalents ('raw', 'logical', 'integer', 'numeric'). |
paths |
A 'character' vector of the paths to the files where the data are stored. If 'NULL', then a temporary file is created using |
filemode |
The read/write mode of the files where the data are stored. This should be 'rb' for read-only access, or 'rb+' for read/write access. |
offset |
A vector giving the offsets in number of bytes from the beginning of each file in 'paths', specifying the start of the data to be accessed for each file. |
extent |
A vector giving the length of the data for each file in 'paths', specifying the number of elements of size 'datamode' to be accessed from each file. |
length |
An optional number giving the total length of the data across all files, equal to the sum of 'extent'. This is ignored and calculated automatically if 'extent' is specified. |
names |
The names of the data elements. |
... |
Additional arguments to be passed to constructor. |
An object of class matter_vec
.
data
:This slot stores the information about locations of the data on disk and within the files.
datamode
:The storage mode of the accessed data when read into R. This is a 'character' vector of length one with value 'integer' or 'numeric'.
paths
:A 'character' vector of the paths to the files where the data are stored.
filemode
:The read/write mode of the files where the data are stored. This should be 'rb' for read-only access, or 'rb+' for read/write access.
chunksize
:The maximum number of elements which should be loaded into memory at once. Used by methods implementing summary statistics and linear algebra. Ignored when explicitly subsetting the dataset.
length
:The length of the data.
dim
:Either 'NULL' for vectors, or an integer vector of length one of more giving the maximal indices in each dimension for matrices and arrays.
names
:The names of the data elements for vectors.
dimnames
:Either 'NULL' or the names for the dimensions. If not 'NULL', then this should be a list of character vectors of the length given by 'dim' for each dimension. This is always 'NULL' for vectors.
ops
:Delayed operations to be applied on atoms.
matter_vec
instances can be created through matter_vec()
or matter()
.
Standard generic methods:
x[i], x[i] <- value
:Get or set the elements of the vector.
c(x, ...)
:Combine vectors.
t(x)
:Transpose a vector (to a row matrix). This is a quick operation which only changes metadata and does not touch the on-disk data.
Kylie A. Bemis
x <- matter_vec(1:100) x[]