R/softmax.R

In hack1nt0/ds.txt:

# fx <- function(X, Y = NULL, ff = list(
#     x.equal.y = function(xi) xi == "澳门",
# ), dtm = T, ngram = 1L, weight = 0L, ...) {
#
#     stopifnot(is.list(X) && all(sapply(X, is.character)) &&
#                   (is.logical(dtm) || is.dtm(dtm)))
#     require(Matrix)
#     if (is.dtm(dtm))
#         A <- dtm
#     else {
#         A <- dtm(X, ngram = ngram, weight = weight, ...)
#         # warning("X is not list of character', entering test mode...")
#         # A <- rsparsematrix(length(X), 2, 0.5)
#         # colnames(A) = c("T1", "T2")
#     }
#     B0 = vector("list", length(ff))
#     names.B0 = vector("character", length(ff))
#     j <- 1L
#     names.ff = names(ff)
#     for (fi in 1:length(ff)) {
#         f = ff[[fi]]
#         col = vector("character", length(X))
#         for (i in 1:length(X)) col[[i]] = f(i)
#         col = as.factor(col)
#         if (nlevels(col) >= 2L) {
#             B0[[j]] = col
#             names.B0[[j]] = ifelse(is.null(names.ff[[fi]]),
#                                    as.character(enquote(body(f)))[[2L]],
#                                    names.ff[[fi]])
#             j = j + 1L
#         }
#         else
#             warning(paste0("Feature function(", names.ff[[fi]], " = ", as.character(enquote(body(f)))[[2L]],
#                            ") should be meaningful (e.g. nlevels(extracted.features) >= 2L), discarded.\n"))
#     }
#     if (j > 1L) {
#         names(B0) = names.B0
#         B <- sparse.model.matrix(~., as.data.frame(B0[1:(j - 1L)]))
#         cbind(B, A)
#     }
#     else {
#         C = cbind(1, A)
#         colnames(C)[[1L]] = "(Intercept)"
#         C
#     }
# }