public String toString() {
		StringBuilder sb = new StringBuilder();
		for( int r=0; r<height; ++r ) {
			if( r != 0 ) sb.append("\n");
			sb.append( r == 0 ? "/" : r == height-1 ? "\\" : "|");
			for( int c=0; c<width; ++c ) {
				sb.append( String.format(" % 5.2f",get(r,c)) );
			}
			sb.append(" ");
			sb.append( r == 0 ? "\\" : r == height-1 ? "/" : "|");
		}
		return sb.toString();
	}