Meta-Analysis using Structural Equation Modeling (metaSEM)
A collection of functions for conducting meta-analysis using a structural equation modeling (SEM) approach via the ‘OpenMx’ package. It also implements the two-stage SEM approach to conduct meta-analytic structural equation modeling on correlation and covariance matrices.

Approximate String Matching and String Distance Functions (stringdist)
Implements an approximate string matching version of R’s native ‘match’ function. Can calculate various string distances based on edits (damerau-levenshtein, hamming, levenshtein, optimal sting alignment), qgrams (q-gram, cosine, jaccard distance) or heuristic metrics (jaro, jaro-winkler). An implementation of soundex is provided as well.

Finding Unique or Duplicated Rows or Columns for Atomic Matrices (uniqueAtomMat)
An alternative implementation and extension (grpDuplicated) of base::duplicated.matrix, base:anyDuplicated.matrix and base::unique.matrix for matrices of atomic mode, avoiding the time consuming collapse of the matrix into a character vector.