{"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":44258,"title":"Outer product of multiple vectors","description":"In tensor algebra, it is often useful to define a tensor as a product of lower order tensors. Similarly, a multidimensional array T might be defined as an outer product of vectors, where a given element is defined by\r\n\r\n  T(i,j,k) = A(i)*B(j)*C(k);\r\n\r\nCreate a function |outerProduct| that accepts any number of row or column vectors and calculates their outer product. For the above example,\r\n\r\n  T = outerProduct(A,B,C);\r\n","description_html":"\u003cp\u003eIn tensor algebra, it is often useful to define a tensor as a product of lower order tensors. Similarly, a multidimensional array T might be defined as an outer product of vectors, where a given element is defined by\u003c/p\u003e\u003cpre class=\"language-matlab\"\u003eT(i,j,k) = A(i)*B(j)*C(k);\r\n\u003c/pre\u003e\u003cp\u003eCreate a function \u003ctt\u003eouterProduct\u003c/tt\u003e that accepts any number of row or column vectors and calculates their outer product. 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Similarly, a multidimensional array T might be defined as an outer product of vectors, where a given element is defined by\r\n\r\n  T(i,j,k) = A(i)*B(j)*C(k);\r\n\r\nCreate a function |outerProduct| that accepts any number of row or column vectors and calculates their outer product. For the above example,\r\n\r\n  T = outerProduct(A,B,C);\r\n","description_html":"\u003cp\u003eIn tensor algebra, it is often useful to define a tensor as a product of lower order tensors. Similarly, a multidimensional array T might be defined as an outer product of vectors, where a given element is defined by\u003c/p\u003e\u003cpre class=\"language-matlab\"\u003eT(i,j,k) = A(i)*B(j)*C(k);\r\n\u003c/pre\u003e\u003cp\u003eCreate a function \u003ctt\u003eouterProduct\u003c/tt\u003e that accepts any number of row or column vectors and calculates their outer product. For the above example,\u003c/p\u003e\u003cpre class=\"language-matlab\"\u003eT = outerProduct(A,B,C);\r\n\u003c/pre\u003e","function_template":"function y = outerProduct(x)\r\n  y = x;\r\nend","test_suite":"%%\r\nfiletext = fileread('outerProduct.m');\r\nassert(~contains(filetext,'regexp'))\r\n\r\n%%\r\ny = outerProduct([],[]);\r\nassert(isempty(y))\r\n\r\n%%\r\nx = randi(100);\r\ny = randi(100);\r\nassert(isequal(outerProduct(x,y),x*y))\r\n\r\n%%\r\nx = randi(100,[1 100]);\r\ny = randi(100,[1 90]);\r\nassert(isequal(outerProduct(x,y),x.'*y))\r\nassert(isequal(outerProduct(x.',y),x.'*y))\r\nassert(isequal(outerProduct(x,y.'),x.'*y))\r\n\r\n%%\r\nx = randi(100,[1 1000]);\r\nxc = num2cell(x);\r\nassert(isequal(outerProduct(xc{:}),prod(x)))","published":true,"deleted":false,"likes_count":3,"comments_count":1,"created_by":1011,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":118,"test_suite_updated_at":null,"rescore_all_solutions":false,"group_id":1,"created_at":"2017-07-10T05:32:47.000Z","updated_at":"2026-04-17T14:18:54.000Z","published_at":"2017-07-10T05:33:24.000Z","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\u003eIn tensor algebra, it is often useful to define a tensor as a product of lower order tensors. 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