{"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":1095,"title":"Circular Primes (based on Project Euler, problem 35)","description":"The number, 197, is called a circular prime because all rotations of the digits: 197, 971, and 719, are themselves prime.\r\n\r\nThere are thirteen such primes below 100: 2, 3, 5, 7, 11, 13, 17, 31, 37, 71, 73, 79, and 97.\r\n\r\nGiven a number x, write a MATLAB script that will tell you the number of circular primes less than or equal to x as well as a sorted list of what the circular prime numbers are.","description_html":"\u003cp\u003eThe number, 197, is called a circular prime because all rotations of the digits: 197, 971, and 719, are themselves prime.\u003c/p\u003e\u003cp\u003eThere are thirteen such primes below 100: 2, 3, 5, 7, 11, 13, 17, 31, 37, 71, 73, 79, and 97.\u003c/p\u003e\u003cp\u003eGiven a number x, write a MATLAB script that will tell you the number of circular primes less than or equal to x as well as a sorted list of what the circular prime numbers are.\u003c/p\u003e","function_template":"function [how_many what_numbers]=circular_prime(x)\r\n    how_many=3;\r\n    what_numbers=[2 3 5];\r\nend","test_suite":"%%\r\n[y numbers]=circular_prime(197)\r\nassert(isequal(y,16)\u0026\u0026isequal(numbers,[2 3 5 7 11 13 17 31 37 71 73 79 97 113 131 197]))\r\n%%\r\n[y numbers]=circular_prime(100)\r\nassert(isequal(y,13)\u0026\u0026isequal(numbers,[2 3 5 7 11 13 17 31 37 71 73 79 97]))\r\n%%\r\n[y numbers]=circular_prime(250)\r\nassert(isequal(y,17)\u0026\u0026isequal(numbers,[2 3 5 7 11 13 17 31 37 71 73 79 97 113 131 197 199]))\r\n%%\r\n[y numbers]=circular_prime(2000)\r\nassert(isequal(y,27)\u0026\u0026isequal(numbers,[2 3 5 7 11 13 17 31 37 71 73 79 97 113 131 197 199 311 337 373 719 733 919 971 991 1193 1931]))\r\n%%\r\n[y numbers]=circular_prime(10000)\r\nassert(isequal(y,33)\u0026\u0026isequal(numbers,[2 3 5 7 11 13 17 31 37 71 73 79 97 113 131 197 199 311 337 373 719 733 919 971 991 1193 1931 3119 3779 7793 7937 9311 9377]))\r\n%%\r\n[y numbers]=circular_prime(54321)\r\nassert(isequal(y,38)\u0026\u0026isequal(numbers,[2 3 5 7 11 13 17 31 37 71 73 79 97 113 131 197 199 311 337 373 719 733 919 971 991 1193 1931 3119 3779 7793 7937 9311 9377 11939 19391 19937 37199 39119]))\r\n","published":true,"deleted":false,"likes_count":10,"comments_count":6,"created_by":1615,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":655,"test_suite_updated_at":null,"rescore_all_solutions":false,"group_id":1,"created_at":"2012-12-05T18:02:09.000Z","updated_at":"2026-05-06T03:26:47.000Z","published_at":"2012-12-05T18:02:09.000Z","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\",\"relationshipId\":\"rId1\",\"target\":\"/matlab/document.xml\"},{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/output\",\"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\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\u003eThe number, 197, is called a circular prime because all rotations of the digits: 197, 971, and 719, are themselves prime.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003cw:jc w:val=\\\"left\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eThere are thirteen such primes below 100: 2, 3, 5, 7, 11, 13, 17, 31, 37, 71, 73, 79, and 97.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003cw:jc w:val=\\\"left\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eGiven a number x, write a MATLAB script that will tell you the number of circular primes less than or equal to x as well as a sorted list of what the circular prime numbers are.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003c/w:body\u003e\u003c/w:document\u003e\"},{\"partUri\":\"/matlab/output.xml\",\"contentType\":\"text/xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\" standalone=\\\"no\\\" ?\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":1095,"title":"Circular Primes (based on Project Euler, problem 35)","description":"The number, 197, is called a circular prime because all rotations of the digits: 197, 971, and 719, are themselves prime.\r\n\r\nThere are thirteen such primes below 100: 2, 3, 5, 7, 11, 13, 17, 31, 37, 71, 73, 79, and 97.\r\n\r\nGiven a number x, write a MATLAB script that will tell you the number of circular primes less than or equal to x as well as a sorted list of what the circular prime numbers are.","description_html":"\u003cp\u003eThe number, 197, is called a circular prime because all rotations of the digits: 197, 971, and 719, are themselves prime.\u003c/p\u003e\u003cp\u003eThere are thirteen such primes below 100: 2, 3, 5, 7, 11, 13, 17, 31, 37, 71, 73, 79, and 97.\u003c/p\u003e\u003cp\u003eGiven a number x, write a MATLAB script that will tell you the number of circular primes less than or equal to x as well as a sorted list of what the circular prime numbers are.\u003c/p\u003e","function_template":"function [how_many what_numbers]=circular_prime(x)\r\n    how_many=3;\r\n    what_numbers=[2 3 5];\r\nend","test_suite":"%%\r\n[y numbers]=circular_prime(197)\r\nassert(isequal(y,16)\u0026\u0026isequal(numbers,[2 3 5 7 11 13 17 31 37 71 73 79 97 113 131 197]))\r\n%%\r\n[y numbers]=circular_prime(100)\r\nassert(isequal(y,13)\u0026\u0026isequal(numbers,[2 3 5 7 11 13 17 31 37 71 73 79 97]))\r\n%%\r\n[y numbers]=circular_prime(250)\r\nassert(isequal(y,17)\u0026\u0026isequal(numbers,[2 3 5 7 11 13 17 31 37 71 73 79 97 113 131 197 199]))\r\n%%\r\n[y numbers]=circular_prime(2000)\r\nassert(isequal(y,27)\u0026\u0026isequal(numbers,[2 3 5 7 11 13 17 31 37 71 73 79 97 113 131 197 199 311 337 373 719 733 919 971 991 1193 1931]))\r\n%%\r\n[y numbers]=circular_prime(10000)\r\nassert(isequal(y,33)\u0026\u0026isequal(numbers,[2 3 5 7 11 13 17 31 37 71 73 79 97 113 131 197 199 311 337 373 719 733 919 971 991 1193 1931 3119 3779 7793 7937 9311 9377]))\r\n%%\r\n[y numbers]=circular_prime(54321)\r\nassert(isequal(y,38)\u0026\u0026isequal(numbers,[2 3 5 7 11 13 17 31 37 71 73 79 97 113 131 197 199 311 337 373 719 733 919 971 991 1193 1931 3119 3779 7793 7937 9311 9377 11939 19391 19937 37199 39119]))\r\n","published":true,"deleted":false,"likes_count":10,"comments_count":6,"created_by":1615,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":655,"test_suite_updated_at":null,"rescore_all_solutions":false,"group_id":1,"created_at":"2012-12-05T18:02:09.000Z","updated_at":"2026-05-06T03:26:47.000Z","published_at":"2012-12-05T18:02:09.000Z","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\",\"relationshipId\":\"rId1\",\"target\":\"/matlab/document.xml\"},{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/output\",\"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\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\u003eThe number, 197, is called a circular prime because all rotations of the digits: 197, 971, and 719, are themselves prime.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003cw:jc w:val=\\\"left\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eThere are thirteen such primes below 100: 2, 3, 5, 7, 11, 13, 17, 31, 37, 71, 73, 79, and 97.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003cw:jc w:val=\\\"left\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eGiven a number x, write a MATLAB script that will tell you the number of circular primes less than or equal to x as well as a sorted list of what the circular prime numbers are.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003c/w:body\u003e\u003c/w:document\u003e\"},{\"partUri\":\"/matlab/output.xml\",\"contentType\":\"text/xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\" standalone=\\\"no\\\" ?\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\"}]}"}],"errors":[],"facets":[[{"value":"Basics - Prime Numbers","count":1,"selected":false},{"value":"Number theory","count":1,"selected":false},{"value":"Project Euler III","count":1,"selected":false},{"value":"The Prime 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