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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).

Type Size Name Uploaded Downloads Labels
conda 203.2 kB | linux-64/r-bit-1.1_12-r3.3.2_0.tar.bz2  7 years and 10 months ago 3884 main cf201901
conda 201.2 kB | linux-64/r-bit-1.1_12-r3.3.1_0.tar.bz2  8 years and 6 months ago 1582 main cf201901
conda 197.7 kB | osx-64/r-bit-1.1_12-r3.2.2_0.tar.bz2  9 years and 27 days ago 3697 main cf201901
conda 199.7 kB | linux-64/r-bit-1.1_12-r3.2.2_0.tar.bz2  9 years and 2 months ago 1050 main cf201901

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