R homework help: monospace ascii art

draw_shape.R

# DrawShape

#' @title Draw Shape
#' @param n height of shape in number of rows
#' @description If n is odd, draw a diamond pattern.
#'   If n is even, draw an hourglass pattern.
#' @note e.g. n = 6
#' #####
#'  ###
#'   #
#'   #
#'  ###
#' #####
#'
#' e.g n = 5
#'    #
#'   ###
#'  #####
#'   ###
#'    #
#'
draw_shape <- function(n){
  if(n %% 2 == 1){
    shape_width <-n
    procession <- odd_procession(n)
  } else {
    shape_width <- n - 1
    procession <- even_procession(n)
  }
  result <- sapply(X=procession, FUN=line_of_symbols, line_length=shape_width)
  cat(result, sep="\n")
}

#' @title Line of Symbols
#' @param num Number of shape symbols on the line
#' @param line_length Length of the line (width of shape)
#' @return A left padded character vector centering the shape symbols.
line_of_symbols <- function(num, line_length){
  padding_char <- ' '
  printed_char <- '#'
  padding_count <- (line_length-num)/2

  character_array <- c(rep(padding_char, padding_count), rep(printed_char, num))

  paste0(character_array, collapse='')
}

#' @title Even Procession
#' @param x even integer height of shape
#' @return A vector of integers of number of symbols per line of shape
#' @note e.g. even_procession(6) #=> 5 3 1 1 3 5
#'   e.g. even_procession(8) #=> 7 5 3 1 1 3 5 7
even_procession <- function(x){
  # YOUR IMPLEMENTATION HERE
  # e.g. return( c(5,3,1,1,3,5) )
}

#' @title Odd Procession
#' @param x odd integer height of shape
#' @return A vector of integers of number of symbols per line of shape
#' @note e.g. odd_procession(5) #=> 1 3 5 3 1
#'   e.g. odd_procession(7) #=> 1 3 5 7 5 3 1
odd_procession <- function(x){
  # YOUR IMPLEMENTATION HERE
  # e.g. return( c(1,3,5,3,1) )
}



### Demo ###
draw_shape(4)
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 #
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draw_shape(5)
  #
 ###
#####
 ###
  #
draw_shape(6)
#####
 ###
  #
  #
 ###
#####
draw_shape(7)
   #
  ###
 #####
#######
 #####
  ###
   #