hcorp: Music Corpora for Harmonic Analysis

#' Popular corpus 1
#'
#' This dataset provides chord sequences for 739 pieces from the
#' McGill Billboard corpus \insertCite{Burgoyne2011}{hcorp}.
#' These pieces were sampled from the Billboard magazine's
#' United States "Hot 100" chart between 1958 and 1991,
#' and transcribed by expert musicians.
#'
#' @details
#' While the original dataset comprises notated chord symbols,
#' this version of the dataset provides a more explicit representation,
#' where each chord is represented as a pitch class set and a labelled
#' bass pitch class.
#' This dataset was used in
#' \insertCite{Harrison2018;textual}{hcorp}.
#'
#' The dataset uses S3 classes from the \code{hrep} package,
#' specifically:
#' \code{\link[hrep]{pc_chord}},
#' for representing chord symbols;
#' \code{\link[hrep]{coded_vec}},
#' for coding chord sequences as integer vectors;
#' \code{\link[hrep]{corpus}},
#' for representing the corpus.
#'
#' Each chord is represented as a 'pitch-class chord':
#' this is defined as a pitch class set with a known bass pitch class.
#' @note \insertCite{Harrison2018;textual}{hcorp}
#' discarded inversion information when modelling this dataset.
#' @name popular_1
#' @docType data
#' @references
#' \insertAllCited{}
#' @keywords data
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