{"group":{"id":1,"name":"Community","lockable":false,"created_at":"2012-01-18T18:02:15.000Z","updated_at":"2026-06-05T00:10:21.000Z","description":"Problems submitted by members of the MATLAB Central community.","is_default":true,"created_by":161519,"badge_id":null,"featured":false,"trending":false,"solution_count_in_trending_period":0,"trending_last_calculated":"2026-06-05T00:00:00.000Z","image_id":null,"published":true,"community_created":false,"status_id":2,"is_default_group_for_player":false,"deleted_by":null,"deleted_at":null,"restored_by":null,"restored_at":null,"description_opc":null,"description_html":null,"published_at":null},"problems":[{"id":1100,"title":"Design matrix from eigenvalues","description":"Write a function that takes one input argument n and outputs a (n x n) square matrix A with the following properties:\r\n\r\n -A has an eigenvalue of 3\r\n\r\n -all elements of A differ more than .5 from each other.\r\n\r\n   For example\r\n\r\nA=matrix_design(3)\r\n \r\nA= 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