{"group":{"id":1,"name":"Community","lockable":false,"created_at":"2012-01-18T18:02:15.000Z","updated_at":"2026-05-26T00:16:20.000Z","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":"2026-05-26T00:00:00.000Z","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":1090,"title":"Create a random logical vector of N elements of which M are true.","description":"Your task for tomorrow is to create a random binary (logical) vector of N elements of which M are true.\r\n\r\nFor example:\r\n\r\n  random_binary(10,4)\r\n\r\ncould result in \r\n\r\n  [1 0 0 1 1 0 0 0 1 0]\r\n\r\nThis task is related to \u003chttp://www.mathworks.nl/matlabcentral/cody/problems/1089 problem 1089\u003e.","description_html":"\u003cp\u003eYour task for tomorrow is to create a random binary (logical) vector of N elements of which M are true.\u003c/p\u003e\u003cp\u003eFor example:\u003c/p\u003e\u003cpre class=\"language-matlab\"\u003erandom_binary(10,4)\r\n\u003c/pre\u003e\u003cp\u003ecould result in\u003c/p\u003e\u003cpre class=\"language-matlab\"\u003e[1 0 0 1 1 0 0 0 1 0]\r\n\u003c/pre\u003e\u003cp\u003eThis task is related to \u003ca href=\"http://www.mathworks.nl/matlabcentral/cody/problems/1089\"\u003eproblem 1089\u003c/a\u003e.\u003c/p\u003e","function_template":"function y = random_binary(n,m)\r\n  y = true(1,n);\r\nend","test_suite":"%%\r\nn = 10;\r\nm = 4;\r\ny = random_binary(n,m);\r\nassert(islogical(y) \u0026\u0026 isequal(sum(y),m) \u0026\u0026 abs(std(diff(y)\u003e0)-0.45)\u003c0.2)\r\n\r\n%%\r\nn = 1000;\r\nm = 500;\r\ny = random_binary(n,m);\r\nassert(islogical(y) \u0026\u0026 isequal(sum(y),m) \u0026\u0026 abs(std(diff(y)\u003e0)-0.45)\u003c0.05)\r\n\r\n%%\r\nn = 500;\r\nm = 20;\r\ny = random_binary(n,m);\r\nassert(islogical(y) \u0026\u0026 isequal(sum(y),m) \u0026\u0026 abs(std(diff(y)\u003e0)-0.18)\u003c0.05)\r\n\r\n","published":true,"deleted":false,"likes_count":1,"comments_count":1,"created_by":6556,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":104,"test_suite_updated_at":null,"rescore_all_solutions":false,"group_id":1,"created_at":"2012-12-04T10:13:03.000Z","updated_at":"2026-05-31T03:14:17.000Z","published_at":"2012-12-04T10:13:03.000Z","restored_at":null,"restored_by":null,"spam":false,"simulink":false,"admin_reviewed":false,"description_opc":"{\"relationships\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/document\",\"targetMode\":\"\",\"relationshipId\":\"rId1\",\"target\":\"/matlab/document.xml\"},{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/output\",\"targetMode\":\"\",\"relationshipId\":\"rId2\",\"target\":\"/matlab/output.xml\"}],\"parts\":[{\"partUri\":\"/matlab/document.xml\",\"relationship\":[],\"contentType\":\"application/vnd.mathworks.matlab.code.document+xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\"?\u003e\\n\u003cw:document xmlns:w=\\\"http://schemas.openxmlformats.org/wordprocessingml/2006/main\\\"\u003e\u003cw:body\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eYour task for tomorrow is to create a random binary (logical) vector of N elements of which M are true.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eFor example:\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"code\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003e\u003c![CDATA[random_binary(10,4)]]\u003e\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003ecould result 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?\u003e\u003cembeddedOutputs\u003e\u003cmetaData\u003e\u003cevaluationState\u003emanual\u003c/evaluationState\u003e\u003clayoutState\u003ecode\u003c/layoutState\u003e\u003coutputStatus\u003eready\u003c/outputStatus\u003e\u003c/metaData\u003e\u003coutputArray type=\\\"array\\\"/\u003e\u003cregionArray type=\\\"array\\\"/\u003e\u003c/embeddedOutputs\u003e\"}]}"}],"problem_search":{"problems":[{"id":1090,"title":"Create a random logical vector of N elements of which M are true.","description":"Your task for tomorrow is to create a random binary (logical) vector of N elements of which M are true.\r\n\r\nFor example:\r\n\r\n  random_binary(10,4)\r\n\r\ncould result in \r\n\r\n  [1 0 0 1 1 0 0 0 1 0]\r\n\r\nThis task is related to \u003chttp://www.mathworks.nl/matlabcentral/cody/problems/1089 problem 1089\u003e.","description_html":"\u003cp\u003eYour task for tomorrow is to create a random binary (logical) vector of N elements of which M are true.\u003c/p\u003e\u003cp\u003eFor example:\u003c/p\u003e\u003cpre class=\"language-matlab\"\u003erandom_binary(10,4)\r\n\u003c/pre\u003e\u003cp\u003ecould result in\u003c/p\u003e\u003cpre class=\"language-matlab\"\u003e[1 0 0 1 1 0 0 0 1 0]\r\n\u003c/pre\u003e\u003cp\u003eThis task is related to \u003ca href=\"http://www.mathworks.nl/matlabcentral/cody/problems/1089\"\u003eproblem 1089\u003c/a\u003e.\u003c/p\u003e","function_template":"function y = random_binary(n,m)\r\n  y = true(1,n);\r\nend","test_suite":"%%\r\nn = 10;\r\nm = 4;\r\ny = random_binary(n,m);\r\nassert(islogical(y) \u0026\u0026 isequal(sum(y),m) \u0026\u0026 abs(std(diff(y)\u003e0)-0.45)\u003c0.2)\r\n\r\n%%\r\nn = 1000;\r\nm = 500;\r\ny = random_binary(n,m);\r\nassert(islogical(y) \u0026\u0026 isequal(sum(y),m) \u0026\u0026 abs(std(diff(y)\u003e0)-0.45)\u003c0.05)\r\n\r\n%%\r\nn = 500;\r\nm = 20;\r\ny = random_binary(n,m);\r\nassert(islogical(y) \u0026\u0026 isequal(sum(y),m) \u0026\u0026 abs(std(diff(y)\u003e0)-0.18)\u003c0.05)\r\n\r\n","published":true,"deleted":false,"likes_count":1,"comments_count":1,"created_by":6556,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":104,"test_suite_updated_at":null,"rescore_all_solutions":false,"group_id":1,"created_at":"2012-12-04T10:13:03.000Z","updated_at":"2026-05-31T03:14:17.000Z","published_at":"2012-12-04T10:13:03.000Z","restored_at":null,"restored_by":null,"spam":false,"simulink":false,"admin_reviewed":false,"description_opc":"{\"relationships\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/document\",\"targetMode\":\"\",\"relationshipId\":\"rId1\",\"target\":\"/matlab/document.xml\"},{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/output\",\"targetMode\":\"\",\"relationshipId\":\"rId2\",\"target\":\"/matlab/output.xml\"}],\"parts\":[{\"partUri\":\"/matlab/document.xml\",\"relationship\":[],\"contentType\":\"application/vnd.mathworks.matlab.code.document+xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\"?\u003e\\n\u003cw:document xmlns:w=\\\"http://schemas.openxmlformats.org/wordprocessingml/2006/main\\\"\u003e\u003cw:body\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eYour task for tomorrow is to create a random binary (logical) vector of N elements of which M are true.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eFor example:\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"code\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003e\u003c![CDATA[random_binary(10,4)]]\u003e\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003ecould result 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