public String asVectorString() {
			if (this.rows.length != 1) {
				throw new IllegalArgumentException("I'm not a vector!");
			}
			
			StringBuilder sb = new StringBuilder();
			Node current = this.rows[0];
			for (int colIndex = 0; colIndex < this.numCols; colIndex++) {
				if (current != null && colIndex == current.colIndex) {
					sb.append(current);
					current = current.next;
				} else {
					sb.append("\tN");
				}
				sb.append("\n");
			}
			
			return sb.toString();
		}