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parallelDist

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Velocity0.0

Parallel Distance Matrix Computation using Multiple Threads

github.com/alexeckert/parallelDist ↗

parallelDist is in pure preservation mode — one build fix every few years.

distance-matrixparallel-computingrcppmaintenance-modecran-compat
◆Current state
parallelDist computes distance matrices across threads in C++ via RcppParallel and Armadillo. The feature set has been settled since 0.2.3 in 2018, which added hamming distance and cosine similarity; everything after that is compatibility work. The most recent release, 0.2.7, exists only to drop a C++11 pin that newer Armadillo versions no longer tolerate.
◆Where it's heading
The package is being kept installable, not developed. The three most recent releases are a toolchain pin removal, a DESCRIPTION field removal, and a coercion change inherited from proxy — none originate from user-facing intent. Gaps of three to four years between releases are the norm now, and each one is triggered by something upstream breaking rather than by a roadmap.
◆Prediction
The next release will almost certainly be another compatibility fix timed to whatever Armadillo, Rcpp or CRAN check policy changes next. Nothing in the entries points to new distance measures or API work.

◆Recent moves

  1. 10mo ago

    parallelDist 0.2.7 drops the C++11 pin for newer Armadillo

    A toolchain fix with no behavioral change: the explicit C++11 dependency is removed so the package keeps compiling against current Armadillo. This is exactly the kind of upstream-triggered release that now defines the package's cadence.

    View source ↗
  2. 4y ago

    parallelDist 0.2.6: LazyData removed, vignette font swapped

    CRAN housekeeping — a DESCRIPTION field drop and a vignette font change. Nothing reaches the distance computation itself.

    View source ↗
  3. 4y ago

    parallelDist 0.2.5 changes cosine distance to 1-x

    Cosine similarity now converts to distance as 1-x rather than 1-abs(x), tracking a change in proxy 0.4-26. Small in code, but it silently changes results for anyone using that measure on signed data, which makes it worth more than a footnote.

    View source ↗
  4. 7y ago

    parallelDist 0.2.4 fixes the Solaris build

    Explicit casts to satisfy the Solaris toolchain — a CRAN platform obligation of the era, invisible to users on any other system.

    View source ↗
  5. 7y ago

    parallelDist 0.2.3 adds hamming and cosine measures

    The last release that grew the package: hamming distance and cosine similarity arrive from contributors, dist labels are preserved, and Minkowski accepts doubles. Everything since has been compatibility work, which makes this the effective end of feature development.

    View source ↗
  6. 7y ago

    parallelDist 0.2.2

    A genuine correctness fix: DTW distances were wrong for matrices of differing length when multiple threads were in use, which is the failure mode a parallel distance package can least afford. CRAN test count was trimmed in the same release.

    View source ↗