Read 'Matlab' files

A compatible reader that can read both 'Matlab' files prior and after version 6.0

Usage

read_mat(file, ram = TRUE, engine = c("r", "py"))

read_mat2(file, ram = TRUE, engine = c("r", "py"))

Arguments

file

path to a 'Matlab' file

ram

whether to load data into memory. Only available when the file is in 'HDF5' format. Default is false and will load arrays, if set to true, then lazy-load data. This is useful when array is very large.

engine

method to read the file, choices are 'r' and 'py' ('Python'); if 'py' is chosen, make sure configure_conda is configured.

Value

A list of All the data stored in the file

Details

io_read_mat can only read 'Matlab' files prior to version 6. After version 6, 'Matlab' uses 'HDF5' format to store its data, and read_mat can handle both cases.

The performance of read_mat can be limited when the file is too big or has many datasets as it reads all the data contained in 'Matlab' file into memory.

See also

io_read_mat, load_h5

Examples

# Matlab .mat <= v7.3
x <- matrix(1:16, 4)
f <- tempfile()
ieegio::io_write_mat(list(x = x), con = f)

read_mat(f)
#> Using native approach to load the matlab file (supporting MAT 5.0)...
#> $x
#>      [,1] [,2] [,3] [,4]
#> [1,]    1    5    9   13
#> [2,]    2    6   10   14
#> [3,]    3    7   11   15
#> [4,]    4    8   12   16
#> 
#> attr(,"header")
#> attr(,"header")$description
#> [1] "MATLAB 5.0 MAT-file, Platform: unix, Software: R v4.4.2, Created on: Sat Feb 15 19:28:49 2025                               "
#> 
#> attr(,"header")$version
#> [1] "5"
#> 
#> attr(,"header")$endian
#> [1] "little"
#> 

# Matlab .mat >= v7.3, using hdf5
# Make sure you have installed hdf5r
if( dipsaus::package_installed('hdf5r') ){

f <- tempfile()
save_h5(x, file = f, name = 'x')

read_mat(f)

# For v7.3, you don't have to load all data into RAM
dat <- read_mat(f, ram = FALSE)
dat

dat$x[]

}
#> /var/folders/2s/h6hvv9ps03xgz_krkkstvq_r0000gn/T//Rtmp64Vhbn/file1e4a340d981d => x (Dataset Created)
#> /var/folders/2s/h6hvv9ps03xgz_krkkstvq_r0000gn/T//Rtmp64Vhbn/file1e4a340d981d => x (Dataset Removed)
#> /var/folders/2s/h6hvv9ps03xgz_krkkstvq_r0000gn/T//Rtmp64Vhbn/file1e4a340d981d => x (Dataset Created)
#>      [,1] [,2] [,3] [,4]
#> [1,]    1    5    9   13
#> [2,]    2    6   10   14
#> [3,]    3    7   11   15
#> [4,]    4    8   12   16