Im making a program where you give 2 inputs, the amount of columns and amount of rows to a multiplikation-system. But when having bigger numbers (2 digit numbers) it makes the system unaligned.
Theres nothing wrong with the code. All I want is something that makes the "|" aligned vertically.
I want the output to be;
| 3 | 6 | 9 |
| 4 | 8 | 12 |
| 6 | 12 | 18 |
But I get the output;
| 3 | 6 | 9 |
| 4 | 8 | 12 |
| 6 | 12 | 18 |
arr = [3, 6, 9, 4, 8, 12, 6, 12, 18]
nrows = 3
width = arr.minmax.map { |n| n.to_s.size }.max
#=> 2
puts arr.each_slice(nrows).map { |row| '| ' +
row.map { |n| "%-#{width}d" % n }.join(' | ') + ' |' }
| 3 | 6 | 9 |
| 4 | 8 | 12 |
| 6 | 12 | 18 |
Perhaps you'd prefer to right-adjust:
puts arr.each_slice(nrows).map { |row| '| ' +
row.map { |n| "%#{width}d" % n }.join(' | ') + ' |' }
| 3 | 6 | 9 |
| 4 | 8 | 12 |
| 6 | 12 | 18 |
See Kernel#sprintf for formatting directives. If it is known that all elements of arr are non-negative we could write:
width = arr.max.to_s.size
#=> 2
If you wish to make each column as narrow as possible, adjusting right, you could do the following.
arr = [3, 6, 9, 4, -81, 12, 6, 12, 1800]
nrows = 3
col_widths = nrows.times.map { |i|
(i..nrows*nrows-1).step(3).map { |j| arr[j].to_s.size }.max }
#=> [1, 3, 4]
puts arr.each_slice(nrows).map { |row| '| ' +
row.map.with_index { |n,i| "%#{col_widths[i]}d" % n }.join(' | ') + ' |' }
| 3 | 6 | 9 |
| 4 | -81 | 12 |
| 6 | 12 | 1800 |
