{"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":2012,"title":"Tony's trick for duplicating an mx1 vector n times","description":"Without using repmat, or for loop, or concatenation, create a function to duplicate a vector, v, a specified number of times, n. v can be numeric or character. n may be 0.\r\n\r\nExamples\r\n\r\nIf\r\n\r\n v = 5;\r\n n = 3;\r\n\r\nthen return v1:\r\n\r\n v1 = [5 5 5] \r\n\r\nIf a 2d matrix is supplied then the vector v will be the first column.\r\n\r\n V = magic(4);\r\n n = 4;\r\n\r\nthen v and v1 are returned as shown below.\r\n\r\n v = [16 5 9 4]'\r\n v1 = [16 16 16 16; 5 5 5 5; 9 9 9 9; 4 4 4 4] \r\n\r\nHint: use indexing\r\n","description_html":"\u003cp\u003eWithout using repmat, or for loop, or concatenation, create a function to duplicate a vector, v, a specified number of times, n. v can be numeric or character. n may be 0.\u003c/p\u003e\u003cp\u003eExamples\u003c/p\u003e\u003cp\u003eIf\u003c/p\u003e\u003cpre\u003e v = 5;\r\n n = 3;\u003c/pre\u003e\u003cp\u003ethen return v1:\u003c/p\u003e\u003cpre\u003e v1 = [5 5 5] \u003c/pre\u003e\u003cp\u003eIf a 2d matrix is supplied then the vector v will be the first column.\u003c/p\u003e\u003cpre\u003e V = magic(4);\r\n n = 4;\u003c/pre\u003e\u003cp\u003ethen v and v1 are returned as shown below.\u003c/p\u003e\u003cpre\u003e v = [16 5 9 4]'\r\n v1 = [16 16 16 16; 5 5 5 5; 9 9 9 9; 4 4 4 4] \u003c/pre\u003e\u003cp\u003eHint: use indexing\u003c/p\u003e","function_template":"function v1 = reproduce_nv(v,n)\r\n  v1 = v;\r\nend","test_suite":"%%\r\nx=magic(3);\r\nn=3;\r\ny_correct=[8 8 8; 3 3 3; 4 4 4];\r\nassert(isequal(reproduce_nv(x,n),y_correct))\r\n\r\n%%\r\nx=magic(10);\r\nn=19;\r\ny_correct=repmat(x(:,1),1,19);\r\nassert(isequal(reproduce_nv(x,n),y_correct))\r\n\r\n%% \r\nx=1;\r\nn=0;\r\ny_correct=linspace(x,x,n); %arbitrary way to get the soln\r\nassert(isequal(reproduce_nv(x,n),y_correct))\r\n\r\n%%\r\nx='1';\r\nn=7;\r\ny_correct=['1' '1' '1' '1' '1' '1' '1'];\r\nassert(isequal(reproduce_nv(x,n),y_correct))\r\n\r\n\r\n","published":true,"deleted":false,"likes_count":1,"comments_count":2,"created_by":17471,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":58,"test_suite_updated_at":null,"rescore_all_solutions":false,"group_id":1,"created_at":"2013-11-23T08:42:47.000Z","updated_at":"2026-04-02T12:30:19.000Z","published_at":"2013-11-23T08:48:28.000Z","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\u003eWithout using repmat, or for loop, or concatenation, create a function to duplicate a vector, v, a specified number of times, n. v can be numeric or character. n may be 0.\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\u003eExamples\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\u003eIf\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[ v = 5;\\n n = 3;]]\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\u003ethen return v1:\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[ v1 = [5 5 5]]]\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\u003eIf a 2d matrix is supplied then the vector v will be the first column.\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[ V = magic(4);\\n n = 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\u003ethen v and v1 are returned as shown below.\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[ v = [16 5 9 4]'\\n v1 = [16 16 16 16; 5 5 5 5; 9 9 9 9; 4 4 4 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\u003eHint: use indexing\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":2012,"title":"Tony's trick for duplicating an mx1 vector n times","description":"Without using repmat, or for loop, or concatenation, create a function to duplicate a vector, v, a specified number of times, n. v can be numeric or character. n may be 0.\r\n\r\nExamples\r\n\r\nIf\r\n\r\n v = 5;\r\n n = 3;\r\n\r\nthen return v1:\r\n\r\n v1 = [5 5 5] \r\n\r\nIf a 2d matrix is supplied then the vector v will be the first column.\r\n\r\n V = magic(4);\r\n n = 4;\r\n\r\nthen v and v1 are returned as shown below.\r\n\r\n v = [16 5 9 4]'\r\n v1 = [16 16 16 16; 5 5 5 5; 9 9 9 9; 4 4 4 4] \r\n\r\nHint: use indexing\r\n","description_html":"\u003cp\u003eWithout using repmat, or for loop, or concatenation, create a function to duplicate a vector, v, a specified number of times, n. v can be numeric or character. n may be 0.\u003c/p\u003e\u003cp\u003eExamples\u003c/p\u003e\u003cp\u003eIf\u003c/p\u003e\u003cpre\u003e v = 5;\r\n n = 3;\u003c/pre\u003e\u003cp\u003ethen return v1:\u003c/p\u003e\u003cpre\u003e v1 = [5 5 5] \u003c/pre\u003e\u003cp\u003eIf a 2d matrix is supplied then the vector v will be the first column.\u003c/p\u003e\u003cpre\u003e V = magic(4);\r\n n = 4;\u003c/pre\u003e\u003cp\u003ethen v and v1 are returned as shown below.\u003c/p\u003e\u003cpre\u003e v = [16 5 9 4]'\r\n v1 = [16 16 16 16; 5 5 5 5; 9 9 9 9; 4 4 4 4] \u003c/pre\u003e\u003cp\u003eHint: use indexing\u003c/p\u003e","function_template":"function v1 = reproduce_nv(v,n)\r\n  v1 = v;\r\nend","test_suite":"%%\r\nx=magic(3);\r\nn=3;\r\ny_correct=[8 8 8; 3 3 3; 4 4 4];\r\nassert(isequal(reproduce_nv(x,n),y_correct))\r\n\r\n%%\r\nx=magic(10);\r\nn=19;\r\ny_correct=repmat(x(:,1),1,19);\r\nassert(isequal(reproduce_nv(x,n),y_correct))\r\n\r\n%% \r\nx=1;\r\nn=0;\r\ny_correct=linspace(x,x,n); %arbitrary way to get the soln\r\nassert(isequal(reproduce_nv(x,n),y_correct))\r\n\r\n%%\r\nx='1';\r\nn=7;\r\ny_correct=['1' '1' '1' '1' '1' '1' '1'];\r\nassert(isequal(reproduce_nv(x,n),y_correct))\r\n\r\n\r\n","published":true,"deleted":false,"likes_count":1,"comments_count":2,"created_by":17471,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":58,"test_suite_updated_at":null,"rescore_all_solutions":false,"group_id":1,"created_at":"2013-11-23T08:42:47.000Z","updated_at":"2026-04-02T12:30:19.000Z","published_at":"2013-11-23T08:48:28.000Z","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\u003eWithout using repmat, or for loop, or concatenation, create a function to duplicate a vector, v, a specified number of times, n. v can be numeric or character. n may be 0.\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\u003eExamples\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\u003eIf\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[ v = 5;\\n n = 3;]]\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\u003ethen return v1:\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[ v1 = [5 5 5]]]\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\u003eIf a 2d matrix is supplied then the vector v will be the first column.\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[ V = magic(4);\\n n = 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\u003ethen v and v1 are returned as shown below.\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[ v = [16 5 9 4]'\\n v1 = [16 16 16 16; 5 5 5 5; 9 9 9 9; 4 4 4 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\u003eHint: use indexing\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":"medium","count":1,"selected":false}]],"term":"tag:\"duplicating vectors\"","page":1,"per_page":50,"sort":"map(difficulty_value,0,0,999) asc"}}