bitmapped vectors of booleans (no NAs), coercion from and to logicals, integers and integer subscripts; fast boolean operators and fast summary statistics. With 'bit' vectors you can store true binary booleans {FALSE,TRUE} at the expense of 1 bit only, on a 32 bit architecture this means factor 32 less RAM and ~ factor 32 more speed on boolean operations. Due to overhead of R calls, actual speed gain depends on the size of the vector: expect gains for vectors of size > 10000 elements. Even for one-time boolean operations it can pay-off to convert to bit, the pay-off is obvious, when such components are used more than once. Reading from and writing to bit is approximately as fast as accessing standard logicals - mostly due to R's time for memory allocation. The package allows to work with pre-allocated memory for return values by calling .Call() directly: when evaluating the speed of C-access with pre-allocated vector memory, coping from bit to logical requires only 70% of the time for copying from logical to logical; and copying from logical to bit comes at a performance penalty of 150%. the package now contains further classes for representing logical selections: 'bitwhich' for very skewed selections and 'ri' for selecting ranges of values for chunked processing. All three index classes can be used for subsetting 'ff' objects (ff-2.1-0 and higher).
18 lines
426 B
Makefile
18 lines
426 B
Makefile
# $NetBSD: Makefile,v 1.1 2018/03/06 17:06:28 minskim Exp $
|
|
|
|
CATEGORIES= devel
|
|
MASTER_SITES= ${MASTER_SITE_R_CRAN:=contrib/}
|
|
|
|
MAINTAINER= minskim@NetBSD.org
|
|
HOMEPAGE= http://ff.r-forge.r-project.org/
|
|
COMMENT= Class for vectors of 1-bit booleans
|
|
LICENSE= gnu-gpl-v2
|
|
|
|
R_PKGNAME= bit
|
|
R_PKGVER= 1.1-12
|
|
|
|
USE_LANGUAGES= c
|
|
|
|
BUILDLINK_API_DEPENDS.R+= R>=2.9.2
|
|
.include "../../math/R/Makefile.extension"
|
|
.include "../../mk/bsd.pkg.mk"
|