[R] maintenance Apr 2017 (#2237)

* [R] make sure things work for a single split model; fixes #2191

* [R] add option use_int_id to xgb.model.dt.tree

* [R] add example of exporting tree plot to a file

* [R] set save_period = NULL as default in xgboost() to be the same as in xgb.train; fixes #2182

* [R] it's a good practice after CRAN releases to bump up package version in dev

* [R] allow xgb.DMatrix construction from integer dense matrices

* [R] xgb.DMatrix: silent parameter; improve documentation

* [R] xgb.model.dt.tree code style changes

* [R] update NEWS with parameter changes

* [R] code safety & style; handle non-strict matrix and inherited classes of input and model; fixes #2242

* [R] change to x.y.z.p R-package versioning scheme and set version to 0.6.4.3

* [R] add an R package versioning section to the contributors guide

* [R] R-package/README.md: clean up the redundant old installation instructions, link the contributors guide
This commit is contained in:
Vadim Khotilovich
2017-05-02 00:51:34 -05:00
committed by Tong He
parent d769b6bcb5
commit a375ad2822
29 changed files with 351 additions and 246 deletions

View File

@@ -14,6 +14,8 @@
#' It could be useful, e.g., in multiclass classification to get only
#' the trees of one certain class. IMPORTANT: the tree index in xgboost models
#' is zero-based (e.g., use \code{trees = 0:4} for first 5 trees).
#' @param use_int_id a logical flag indicating whether nodes in columns "Yes", "No", "Missing" should be
#' represented as integers (when FALSE) or as "Tree-Node" character strings (when FALSE).
#' @param ... currently not used.
#'
#' @return
@@ -22,9 +24,9 @@
#' The columns of the \code{data.table} are:
#'
#' \itemize{
#' \item \code{Tree}: ID of a tree in a model (integer)
#' \item \code{Node}: integer ID of a node in a tree (integer)
#' \item \code{ID}: identifier of a node in a model (character)
#' \item \code{Tree}: integer ID of a tree in a model (zero-based index)
#' \item \code{Node}: integer ID of a node in a tree (zero-based index)
#' \item \code{ID}: character identifier of a node in a model (only when \code{use_int_id=FALSE})
#' \item \code{Feature}: for a branch node, it's a feature id or name (when available);
#' for a leaf note, it simply labels it as \code{'Leaf'}
#' \item \code{Split}: location of the split for a branch node (split condition is always "less than")
@@ -36,6 +38,10 @@
#' or collected by a leaf during training.
#' }
#'
#' When \code{use_int_id=FALSE}, columns "Yes", "No", and "Missing" point to model-wide node identifiers
#' in the "ID" column. When \code{use_int_id=TRUE}, those columns point to node identifiers from
#' the corresponding trees in the "Node" column.
#'
#' @examples
#' # Basic use:
#'
@@ -45,8 +51,9 @@
#' eta = 1, nthread = 2, nrounds = 2,objective = "binary:logistic")
#'
#' (dt <- xgb.model.dt.tree(colnames(agaricus.train$data), bst))
#' # This bst has feature_names stored in it, so those would be used when
#' # the feature_names parameter is not provided:
#'
#' # This bst model already has feature_names stored with it, so those would be used when
#' # feature_names is not set:
#' (dt <- xgb.model.dt.tree(model = bst))
#'
#' # How to match feature names of splits that are following a current 'Yes' branch:
@@ -55,24 +62,24 @@
#'
#' @export
xgb.model.dt.tree <- function(feature_names = NULL, model = NULL, text = NULL,
trees = NULL, ...){
trees = NULL, use_int_id = FALSE, ...){
check.deprecation(...)
if (class(model) != "xgb.Booster" & class(text) != "character") {
stop("Either 'model' has to be an object of class xgb.Booster\n",
" or 'text' has to be a character vector with the result of xgb.dump\n",
" (or NULL if the model was provided).")
if (!inherits(model, "xgb.Booster") & !is.character(text)) {
stop("Either 'model' must be an object of class xgb.Booster\n",
" or 'text' must be a character vector with the result of xgb.dump\n",
" (or NULL if 'model' was provided).")
}
if (is.null(feature_names) && !is.null(model) && !is.null(model$feature_names))
feature_names <- model$feature_names
if (!class(feature_names) %in% c("character", "NULL")) {
stop("feature_names: Has to be a character vector")
if (!(is.null(feature_names) || is.character(feature_names))) {
stop("feature_names: must be a character vector")
}
if (!class(trees) %in% c("integer", "numeric", "NULL")) {
stop("trees: Has to be a vector of integers.")
if (!(is.null(trees) || is.numeric(trees))) {
stop("trees: must be a vector of integers.")
}
if (is.null(text)){
@@ -86,11 +93,11 @@ xgb.model.dt.tree <- function(feature_names = NULL, model = NULL, text = NULL,
position <- which(!is.na(stri_match_first_regex(text, "booster")))
add.tree.id <- function(x, i) paste(i, x, sep = "-")
add.tree.id <- function(node, tree) if (use_int_id) node else paste(tree, node, sep = "-")
anynumber_regex <- "[-+]?[0-9]*\\.?[0-9]+([eE][-+]?[0-9]+)?"
td <- data.table(t=text)
td <- data.table(t = text)
td[position, Tree := 1L]
td[, Tree := cumsum(ifelse(is.na(Tree), 0L, Tree)) - 1L]
@@ -102,32 +109,43 @@ xgb.model.dt.tree <- function(feature_names = NULL, model = NULL, text = NULL,
td <- td[Tree %in% trees & !grepl('^booster', t)]
td[, Node := stri_match_first_regex(t, "(\\d+):")[,2] %>% as.integer ]
td[, ID := add.tree.id(Node, Tree)]
if (!use_int_id) td[, ID := add.tree.id(Node, Tree)]
td[, isLeaf := !is.na(stri_match_first_regex(t, "leaf"))]
# parse branch lines
td[isLeaf==FALSE, c("Feature", "Split", "Yes", "No", "Missing", "Quality", "Cover") := {
rx <- paste0("f(\\d+)<(", anynumber_regex, ")\\] yes=(\\d+),no=(\\d+),missing=(\\d+),",
"gain=(", anynumber_regex, "),cover=(", anynumber_regex, ")")
# skip some indices with spurious capture groups from anynumber_regex
xtr <- stri_match_first_regex(t, rx)[, c(2,3,5,6,7,8,10)]
xtr[, 3:5] <- add.tree.id(xtr[, 3:5], Tree)
lapply(1:ncol(xtr), function(i) xtr[,i])
}]
branch_rx <- paste0("f(\\d+)<(", anynumber_regex, ")\\] yes=(\\d+),no=(\\d+),missing=(\\d+),",
"gain=(", anynumber_regex, "),cover=(", anynumber_regex, ")")
branch_cols <- c("Feature", "Split", "Yes", "No", "Missing", "Quality", "Cover")
td[isLeaf == FALSE,
(branch_cols) := {
# skip some indices with spurious capture groups from anynumber_regex
xtr <- stri_match_first_regex(t, branch_rx)[, c(2,3,5,6,7,8,10), drop = FALSE]
xtr[, 3:5] <- add.tree.id(xtr[, 3:5], Tree)
lapply(1:ncol(xtr), function(i) xtr[,i])
}]
# assign feature_names when available
td[isLeaf==FALSE & !is.null(feature_names),
Feature := feature_names[as.numeric(Feature) + 1] ]
if (!is.null(feature_names)) {
if (length(feature_names) <= max(as.numeric(td$Feature), na.rm = TRUE))
stop("feature_names has less elements than there are features used in the model")
td[isLeaf == FALSE, Feature := feature_names[as.numeric(Feature) + 1] ]
}
# parse leaf lines
td[isLeaf==TRUE, c("Feature", "Quality", "Cover") := {
rx <- paste0("leaf=(", anynumber_regex, "),cover=(", anynumber_regex, ")")
xtr <- stri_match_first_regex(t, rx)[, c(2,4)]
c("Leaf", lapply(1:ncol(xtr), function(i) xtr[,i]))
}]
leaf_rx <- paste0("leaf=(", anynumber_regex, "),cover=(", anynumber_regex, ")")
leaf_cols <- c("Feature", "Quality", "Cover")
td[isLeaf == TRUE,
(leaf_cols) := {
xtr <- stri_match_first_regex(t, leaf_rx)[, c(2,4)]
c("Leaf", lapply(1:ncol(xtr), function(i) xtr[,i]))
}]
# convert some columns to numeric
numeric_cols <- c("Split", "Quality", "Cover")
td[, (numeric_cols) := lapply(.SD, as.numeric), .SDcols=numeric_cols]
td[, (numeric_cols) := lapply(.SD, as.numeric), .SDcols = numeric_cols]
if (use_int_id) {
int_cols <- c("Yes", "No", "Missing")
td[, (int_cols) := lapply(.SD, as.integer), .SDcols = int_cols]
}
td[, t := NULL]
td[, isLeaf := NULL]