similarities: Similarities for sparse and dense 2d representations
In vspinu/simdist: High performance distance and similarity functions

Similarity counterparts of distances, which see. Generally similarities are computed from their distance counterparts through s=1-d or s=1/(1+d), but this need not always be the case. See the source code for the exact computation.

sim_cosine(x, y = NULL, ptrans = "l2", strans = NULL, by = c("primary",
  "secondary", "row", "column"), ref_names = NULL)

sim_euclidean(x, y = NULL, ptrans = NULL, strans = NULL,
  by = c("primary", "secondary", "row", "column"), ref_names = NULL)

`x`	sparse or dense objects supported by `simdist`. See `simdist-package` for description of supported types and related terminology.
`y`	sparse or dense objects supported by `simdist`. See `simdist-package` for description of supported types and related terminology.
`ptrans`	Primary and secondary transformations. Can be either a function, string or a numeric vector. When a function, it must take 3 arguments - an object supported by `simdist` distance measures, names of a dimension ("primary" or "secondary") and logical na.rm. When a string it must name a transformation function without the semantic prefix (norm_, scale_ or trans_); see `link{transformations}`. When numeric vector it specifies weights to scale along the corresponding dimension.
`strans`	Primary and secondary transformations. Can be either a function, string or a numeric vector. When a function, it must take 3 arguments - an object supported by `simdist` distance measures, names of a dimension ("primary" or "secondary") and logical na.rm. When a string it must name a transformation function without the semantic prefix (norm_, scale_ or trans_); see `link{transformations}`. When numeric vector it specifies weights to scale along the corresponding dimension.
`by`	Dimension along which to perform distance computation. For all supported data structures computation along primary dimension is more or as efficient than along the secondary dimension.
`ref_names`	reference names for secondary entries. By default both `x` and `y` secondary names are used. Secondary entries not in `ref_names` are discarded from `x` and `y`.