Read-Write Support for 'NumPy' Files via 'Rcpp'
The 'cnpy' library written by Carl Rogers provides read and write
facilities for files created with (or for) the 'NumPy' extension for 'Python'.
Vectors and matrices of numeric types can be read or written to and from
files as well as compressed files. Support for integer files is available if
the package has been built with -std=c++11 which should be the default on
all platforms since the release of R 3.3.0.
RcppCNPy: Rcpp bindings for NumPy files
This package uses the cnpy library written by Carl Rogers to provide read and write facilities for files created with (or for) the NumPy extension for Python. Vectors and matrices of numeric types can be read or written to and from files as well as compressed files. Support for integer files is available if the package has been built with -std=c++11 which is the default starting with release 0.2.3 following the release of R 3.1.0, and available on all platforms following the release of R 3.3.0 with the updated 'Rtools'.
The following Python code
>>> import numpy as np >>> fm = np.arange(12).reshape(3,4) * 1.1 >>> fm array([[ 0. , 1.1, 2.2, 3.3], [ 4.4, 5.5, 6.6, 7.7], [ 8.8, 9.9, 11. , 12.1]]) >>> np.save("fmat.npy", fm) >>> >>> im = np.arange(12).reshape(3,4) >>> im array([[ 0, 1, 2, 3], [ 4, 5, 6, 7], [ 8, 9, 10, 11]]) >>> np.save("imat.npy", im) >>>
saves two matrices in floating-point and integer representation.
With this R code we can read and assign the files:
R> library(RcppCNPy) R> fmat <- npyLoad("fmat.npy") R> fmat [,1] [,2] [,3] [,4] [1,] 0.0 1.1 2.2 3.3 [2,] 4.4 5.5 6.6 7.7 [3,] 8.8 9.9 11.0 12.1 R> R> imat <- npyLoad("imat.npy", "integer") R> imat [,1] [,2] [,3] [,4] [1,] 0 1 2 3 [2,] 4 5 6 7 [3,] 8 9 10 11 R>
Going the opposite way by saving in R and reading in Python works equally well. An extension not present in CNPy allows reading and writing of gzip-compressed files.
The package has been tested and used on several architecture, and copes correctly with little-vs-big endian switches.
More details are available in the package vignette.
The package is on CRAN and can be installed per:
On CRAN, stable and mostly feature-complete.
Dirk Eddelbuettel and Wush Wu
GPL (>= 2)
Functions in RcppCNPy
|RcppCNPy-package||File access to data files written by (or for) NumPy (Numeric Python) modules|
Vignettes of RcppCNPy
Last month downloads
|License||GPL (>= 2)|
|Packaged||2018-07-29 19:18:01.11984 UTC; edd|
|Date/Publication||2018-07-29 19:40:03 UTC|
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