软件包:r-cran-bit(1.1-14-1 以及其他的)
GNU R class for vectors of 1-bit booleans
This GNU R package provides 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 one 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).
其他与 r-cran-bit 有关的软件包
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- dep: libc6 (>= 2.1.3) [i386]
- GNU C 语言运行库:共享库
同时作为一个虚包由这些包填实: libc6-udeb
- dep: libc6 (>= 2.17) [arm64]
- dep: libc6 (>= 2.2.5) [amd64]
- dep: libc6 (>= 2.4) [armhf]
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- dep: r-api-3.5
- 本虚包由这些包填实: r-base-core
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- dep: r-base-core (>= 3.5.0-4) [arm64, i386]
- GNU R core of statistical computation and graphics system
- dep: r-base-core (>= 3.5.0-5) [amd64, armhf]