Change Details

WITH RECURSIVE -- Grid of points for which the Mandelbrot set will be approximated xaxis(x) as (VALUES(-2.0) UNION ALL SELECT x+0.05 FROM xaxis WHERE x < 1.2), yaxis(y) as (VALUES(-1.0) UNION ALL SELECT y+0.10 FROM yaxis WHERE y < 1.0), -- Mandelbrot iterations m(iter, cx, cy, x, y) AS ( SELECT 0, x, y, 0.0, 0.0 FROM xaxis, yaxis UNION ALL SELECT iter + 1, cx, cy, x*x - y*y + cx, x*y*(x+y) + cy FROM m WHERE (x*x + y*y) < 4.0 AND iter < 28 ), m2(iter, cx, cy) AS ( SELECT max(iter), cx, cy FROM m GROUP BY cx, cy ), -- ASCII representation line per line a(t) AS ( SELECT group_concat(substr(' .+*#', 1 + min(iter/7, 4), 1), '') FROM m2 GROUP BY cy ) -- All lines SELECT group_concat(rtrim(t), x'0a') FROM a;