R/mathead.R

In jamesdalg/HiCNV: A Versatile Toolkit for Copy Number Variation Relationship Data Analysis and Visualization

#' Gets a small piece of a matrix (top left corner) for viewing, rather than pulling the first n rows.
#'
#' Gives a small square of a matrix to get an idea of content rather than grabbing the entire row.
#' When this row is thousands of numbers long, this can be a problem.
#' @keywords rescale downsample average edges matrix
#' @param mat A matrix.
#' @param n The length and width of the piece to view.
#' @return averaged_matrix a small matrix of size n.
#' @examples 
#' load(system.file("extdata","nbl_result_matrix_sign_small.rda",package = "HiCNV"))
#' mathead(nbl_result_matrix_sign_small)
#' @export

mathead<-function(mat,n=6L)
{
  return(mat[1:n,1:n])
}