Read data from a virtually reshaped HDF5 dataset
An h5mread wrapper that reads data from a virtually
reshaped HDF5 dataset.
h5mread_from_reshaped(filepath, name, dim, starts, noreduce=FALSE,
as.integer=FALSE, method=0L)filepath |
The path (as a single string) to the HDF5 file where the dataset to read from is located. |
name |
The name of the dataset in the HDF5 file. |
dim |
A vector of dimensions that describes the virtual reshaping i.e. the reshaping that is virtually applied upfront to the HDF5 dataset to read from. Note that the HDF5 dataset is treated as read-only so never gets effectively reshaped, that is, the dataset dimensions encoded in the HDF5 file are not mmodified. Also please note that arbitrary reshapings are not supported. Only reshapings that reduce the number of dimensions by collapsing a group of consecutive dimensions into a single dimension are supported. For example, reshaping a 10 x 3 x 5 x 1000 array as a 10 x 15 x 1000 array or as a 150 x 1000 matrix is supported. |
starts |
A multidimensional subsetting index with respect to the reshaped dataset, that is, a list with one list element per dimension in the reshaped dataset. Each list element in |
noreduce, as.integer, method |
See |
An array.
## ---------------------------------------------------------------------
## BASIC USAGE
## ---------------------------------------------------------------------
a1 <- array(1:350, c(10, 5, 7))
A1 <- writeHDF5Array(a1, name="A1")
## Collapse the first 2 dimensions:
h5mread_from_reshaped(path(A1), "A1", dim=c(50, 7),
starts=list(8:11, NULL))
h5mread_from_reshaped(path(A1), "A1", dim=c(50, 7),
starts=list(8:11, NULL))
## Collapse the last 2 dimensions:
h5mread_from_reshaped(path(A1), "A1", dim=c(10, 35),
starts=list(NULL, 3:11))
a2 <- array(1:150000 + 0.1*runif(150000), c(10, 3, 5, 1000))
A2 <- writeHDF5Array(a2, name="A2")
## Collapse the 2nd and 3rd dimensions:
h5mread_from_reshaped(path(A2), "A2", dim=c(10, 15, 1000),
starts=list(NULL, 8:11, 999:1000))
## Collapse the first 3 dimensions:
h5mread_from_reshaped(path(A2), "A2", dim=c(150, 1000),
starts=list(71:110, 999:1000))Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.