{"group":{"id":1,"name":"Community","lockable":false,"created_at":"2012-01-18T18:02:15.000Z","updated_at":"2026-04-06T14:01:22.000Z","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":"2026-04-06T00:00:00.000Z","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":43752,"title":"Vandermonde Matrix","description":"Create the Vandermonde Matrix of the given vector. The matrix consists of columns as powers of the vector, so the first column is the inverse of the vector raised to 0. The second column is the vector raised to 1, etc.\r\n\r\nFor example, given the vector:\r\n\r\n  v=[1 2 3 4 5];\r\n\r\nthe Vandermonde Matrix would be\r\n\r\n  Vm=\r\n     1     1     1     1     1\r\n     1     2     4     8    16\r\n     1     3     9    27    81\r\n     1     4    16    64   256\r\n     1     5    25   125   625\r\n\r\nSee \u003chttps://en.wikipedia.org/wiki/Vandermonde_matrix Vandermonde Matrix\u003e for more details.","description_html":"\u003cp\u003eCreate the Vandermonde Matrix of the given vector. The matrix consists of columns as powers of the vector, so the first column is the inverse of the vector raised to 0. The second column is the vector raised to 1, etc.\u003c/p\u003e\u003cp\u003eFor example, given the vector:\u003c/p\u003e\u003cpre class=\"language-matlab\"\u003ev=[1 2 3 4 5];\r\n\u003c/pre\u003e\u003cp\u003ethe Vandermonde Matrix would be\u003c/p\u003e\u003cpre class=\"language-matlab\"\u003eVm=\r\n   1     1     1     1     1\r\n   1     2     4     8    16\r\n   1     3     9    27    81\r\n   1     4    16    64   256\r\n   1     5    25   125   625\r\n\u003c/pre\u003e\u003cp\u003eSee \u003ca href = \"https://en.wikipedia.org/wiki/Vandermonde_matrix\"\u003eVandermonde Matrix\u003c/a\u003e for more details.\u003c/p\u003e","function_template":"function y = vandimat(x)\r\n  y = x;\r\nend","test_suite":"%%\r\nx = 1:5;\r\ny_correct = [1,1,1,1,1;1,2,4,8,16;1,3,9,27,81;1,4,16,64,256;1,5,25,125,625];\r\nassert(isequal(vandimat(x),y_correct))\r\n%%\r\nx = 1;\r\ny_correct = 1;\r\nassert(isequal(vandimat(x),y_correct))\r\n%%\r\nx = ones(1,20);\r\ny_correct = ones(20);\r\nassert(isequal(vandimat(x),y_correct))\r\n%%\r\nx = 3.*ones(1,15);\r\ny_correct = repmat([1,3,9,27,81,243,729,2187,6561,19683,59049,177147,531441,1594323,4782969],15,1);\r\nassert(isequal(vandimat(x),y_correct))\r\n%%\r\nx = [1 5 2 4 3];\r\ny_correct = [1,1,1,1,1;1,5,25,125,625;1,2,4,8,16;1,4,16,64,256;1,3,9,27,81];\r\nassert(isequal(vandimat(x),y_correct))","published":true,"deleted":false,"likes_count":1,"comments_count":0,"created_by":93456,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":113,"test_suite_updated_at":null,"rescore_all_solutions":false,"group_id":41,"created_at":"2016-12-07T21:54:07.000Z","updated_at":"2026-02-14T08:53:16.000Z","published_at":"2016-12-07T21:54:07.000Z","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\u003eCreate the Vandermonde Matrix of the given vector. The matrix consists of columns as powers of the vector, so the first column is the inverse of the vector raised to 0. The second column is the vector raised to 1, etc.\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, given the vector:\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=[1 2 3 4 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\u003ethe Vandermonde Matrix would be\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[Vm=\\n   1     1     1     1     1\\n   1     2     4     8    16\\n   1     3     9    27    81\\n   1     4    16    64   256\\n   1     5    25   125   625]]\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\u003eSee\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e \u003c/w:t\u003e\u003c/w:r\u003e\u003cw:hyperlink w:docLocation=\\\"https://en.wikipedia.org/wiki/Vandermonde_matrix\\\"\u003e\u003cw:r\u003e\u003cw:t\u003eVandermonde Matrix\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:hyperlink\u003e\u003cw:r\u003e\u003cw:t\u003e for more details.\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":{"errors":[],"problems":[{"id":43752,"title":"Vandermonde Matrix","description":"Create the Vandermonde Matrix of the given vector. The matrix consists of columns as powers of the vector, so the first column is the inverse of the vector raised to 0. The second column is the vector raised to 1, etc.\r\n\r\nFor example, given the vector:\r\n\r\n  v=[1 2 3 4 5];\r\n\r\nthe Vandermonde Matrix would be\r\n\r\n  Vm=\r\n     1     1     1     1     1\r\n     1     2     4     8    16\r\n     1     3     9    27    81\r\n     1     4    16    64   256\r\n     1     5    25   125   625\r\n\r\nSee \u003chttps://en.wikipedia.org/wiki/Vandermonde_matrix Vandermonde Matrix\u003e for more details.","description_html":"\u003cp\u003eCreate the Vandermonde Matrix of the given vector. The matrix consists of columns as powers of the vector, so the first column is the inverse of the vector raised to 0. The second column is the vector raised to 1, etc.\u003c/p\u003e\u003cp\u003eFor example, given the vector:\u003c/p\u003e\u003cpre class=\"language-matlab\"\u003ev=[1 2 3 4 5];\r\n\u003c/pre\u003e\u003cp\u003ethe Vandermonde Matrix would be\u003c/p\u003e\u003cpre class=\"language-matlab\"\u003eVm=\r\n   1     1     1     1     1\r\n   1     2     4     8    16\r\n   1     3     9    27    81\r\n   1     4    16    64   256\r\n   1     5    25   125   625\r\n\u003c/pre\u003e\u003cp\u003eSee \u003ca href = \"https://en.wikipedia.org/wiki/Vandermonde_matrix\"\u003eVandermonde Matrix\u003c/a\u003e for more details.\u003c/p\u003e","function_template":"function y = vandimat(x)\r\n  y = x;\r\nend","test_suite":"%%\r\nx = 1:5;\r\ny_correct = [1,1,1,1,1;1,2,4,8,16;1,3,9,27,81;1,4,16,64,256;1,5,25,125,625];\r\nassert(isequal(vandimat(x),y_correct))\r\n%%\r\nx = 1;\r\ny_correct = 1;\r\nassert(isequal(vandimat(x),y_correct))\r\n%%\r\nx = ones(1,20);\r\ny_correct = ones(20);\r\nassert(isequal(vandimat(x),y_correct))\r\n%%\r\nx = 3.*ones(1,15);\r\ny_correct = repmat([1,3,9,27,81,243,729,2187,6561,19683,59049,177147,531441,1594323,4782969],15,1);\r\nassert(isequal(vandimat(x),y_correct))\r\n%%\r\nx = [1 5 2 4 3];\r\ny_correct = [1,1,1,1,1;1,5,25,125,625;1,2,4,8,16;1,4,16,64,256;1,3,9,27,81];\r\nassert(isequal(vandimat(x),y_correct))","published":true,"deleted":false,"likes_count":1,"comments_count":0,"created_by":93456,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":113,"test_suite_updated_at":null,"rescore_all_solutions":false,"group_id":41,"created_at":"2016-12-07T21:54:07.000Z","updated_at":"2026-02-14T08:53:16.000Z","published_at":"2016-12-07T21:54:07.000Z","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\u003eCreate the Vandermonde Matrix of the given vector. The matrix consists of columns as powers of the vector, so the first column is the inverse of the vector raised to 0. The second column is the vector raised to 1, etc.\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, given the vector:\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=[1 2 3 4 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\u003ethe Vandermonde Matrix would be\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[Vm=\\n   1     1     1     1     1\\n   1     2     4     8    16\\n   1     3     9    27    81\\n   1     4    16    64   256\\n   1     5    25   125   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