{"group":{"id":1,"name":"Community","lockable":false,"created_at":"2012-01-18T18:02:15.000Z","updated_at":"2026-04-16T00:12:35.000Z","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":"2026-04-16T00:00:00.000Z","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":2145,"title":"Find the index of n in magic(n)","description":"If input n=5, then magic(n) is\r\n\r\n    17    24     1     8    15\r\n    23     5     7    14    16\r\n     4     6    13    20    22\r\n    10    12    19    21     3\r\n    11    18    25     2     9\r\n\r\nThe output is of the form [row,column] for the place where n appears.\r\n\r\n output = [2,2]\r\n","description_html":"\u003cp\u003eIf input n=5, then magic(n) is\u003c/p\u003e\u003cpre\u003e    17    24     1     8    15\r\n    23     5     7    14    16\r\n     4     6    13    20    22\r\n    10    12    19    21     3\r\n    11    18    25     2     9\u003c/pre\u003e\u003cp\u003eThe output is of the form [row,column] for the place where n appears.\u003c/p\u003e\u003cpre\u003e output = [2,2]\u003c/pre\u003e","function_template":"function y = nim(x)\r\n  y = x;\r\nend","test_suite":"%%\r\nx = 7;\r\ny_correct = [2,3];\r\nassert(isequal(nim(x),y_correct))\r\n%%\r\nx = 11;\r\ny_correct = [2,5];\r\nassert(isequal(nim(x),y_correct))\r\n%%\r\nx = 3;\r\ny_correct = [2,1];\r\nassert(isequal(nim(x),y_correct))","published":true,"deleted":false,"likes_count":5,"comments_count":1,"created_by":1690,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":273,"test_suite_updated_at":null,"rescore_all_solutions":false,"group_id":21,"created_at":"2014-01-31T07:51:37.000Z","updated_at":"2026-04-01T20:58:17.000Z","published_at":"2014-01-31T07:51:37.000Z","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\u003eIf input n=5, then magic(n) is\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[    17    24     1     8    15\\n    23     5     7    14    16\\n     4     6    13    20    22\\n    10    12    19    21     3\\n    11    18    25     2     9]]\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 output is of the form [row,column] for the place where n appears.\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[ output = [2,2]]]\u003e\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\"}]}"},{"id":1923,"title":"Find the maximum two numbers of every column of a matrix","description":"Find the maximum two numbers of every column of a matrix.\r\n\r\nExample:\r\n\r\nIf we input a matrix \r\n\r\n A = [ 1 2 4\r\n       6 0 3\r\n       4 1 5 ]\r\n\r\nwe should get\r\n\r\n B = [ 6 2 5\r\n       4 1 4 ]\r\n","description_html":"\u003cp\u003eFind the maximum two numbers of every column of a matrix.\u003c/p\u003e\u003cp\u003eExample:\u003c/p\u003e\u003cp\u003eIf we input a matrix\u003c/p\u003e\u003cpre\u003e A = [ 1 2 4\r\n       6 0 3\r\n       4 1 5 ]\u003c/pre\u003e\u003cp\u003ewe should get\u003c/p\u003e\u003cpre\u003e B = [ 6 2 5\r\n       4 1 4 ]\u003c/pre\u003e","function_template":"function y = your_fcn_name(x)\r\n  y = x;\r\nend","test_suite":"%%\r\nx = [1 2 4;\r\n     6 0 3;\r\n     4 1 5];\r\ny_correct = [6 2 5;\r\n             4 1 4];\r\nassert(isequal(your_fcn_name(x),y_correct))\r\n\r\n%%\r\nx = ones(3);\r\ny_correct = ones(2,3);\r\nassert(isequal(your_fcn_name(x),y_correct))\r\n\r\n%%\r\nx = eye(4);\r\ny_correct = [ones(1,4); zeros(1,4)];\r\nassert(isequal(your_fcn_name(x),y_correct))\r\n\r\n%%\r\nx = [1:5;\r\n     6:10;\r\n     11:15;\r\n     16:20;\r\n     21:25];\r\ny_correct = [21:25; 16:20];\r\nassert(isequal(your_fcn_name(x),y_correct))\r\n\r\n%%\r\nx = [1 5 7 3 47 2  3;\r\n     6 7 1 5 23 1 47;\r\n     7 1 3 2 68 4 11];\r\ny_correct = [7 7 7 5 68 4 47;\r\n             6 5 3 3 47 2 11];\r\nassert(isequal(your_fcn_name(x),y_correct))","published":true,"deleted":false,"likes_count":1,"comments_count":1,"created_by":3668,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":231,"test_suite_updated_at":"2017-03-15T16:43:08.000Z","rescore_all_solutions":false,"group_id":21,"created_at":"2013-10-08T14:30:23.000Z","updated_at":"2026-03-31T17:07:39.000Z","published_at":"2013-10-08T14:30:22.000Z","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\u003eFind the maximum two numbers of every column of a matrix.\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\u003eExample:\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 we input a matrix\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[ A = [ 1 2 4\\n       6 0 3\\n       4 1 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\u003ewe should get\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[ B = [ 6 2 5\\n       4 1 4 ]]]\u003e\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\"}]}"},{"id":2476,"title":"Max Change in Consecutive Elements","description":"If an array is given as input then find the index of consecutive elements that represent maximum change.\r\n\r\nExample:\r\n\r\n Input    x = [1 10 3 0 2 4 0 -8 9 1]\r\n\r\n Output   y = [8 9]","description_html":"\u003cp\u003eIf an array is given as input then find the index of consecutive elements that represent maximum change.\u003c/p\u003e\u003cp\u003eExample:\u003c/p\u003e\u003cpre\u003e Input    x = [1 10 3 0 2 4 0 -8 9 1]\u003c/pre\u003e\u003cpre\u003e Output   y = [8 9]\u003c/pre\u003e","function_template":"function y = maxChange(x)\r\n  y = x;\r\nend","test_suite":"%%\r\nx = [1 10 3 0 2 4 0 -8 9 1];\r\ny_correct = [8 9];\r\nassert(isequal(maxChange(x),y_correct))\r\n\r\n%%\r\nx = [10 15 2 18 40];\r\ny_correct = [4 5];\r\nassert(isequal(maxChange(x),y_correct))\r\n\r\n%%\r\nx = 1:10;\r\nx(4) = 0;\r\ny_correct = [4 5];\r\nassert(isequal(maxChange(x),y_correct))\r\n\r\n%%\r\nx = [1 10 100 1e3 1e4 1e5 1e6 1e7];\r\ny_correct = [7 8];\r\nassert(isequal(maxChange(x),y_correct))\r\n\r\n%%\r\nx = [-10 10 -8 7 -5 3 -2 1 -1 0];\r\ny_correct = [1 2];\r\nassert(isequal(maxChange(x),y_correct))\r\n\r\n%%\r\nx = ones(1,1e6);\r\nx(789) = 0; x(788) = 0.5;\r\ny_correct = [789 790];\r\nassert(isequal(maxChange(x),y_correct))","published":true,"deleted":false,"likes_count":3,"comments_count":6,"created_by":16361,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":181,"test_suite_updated_at":"2017-03-15T17:18:53.000Z","rescore_all_solutions":false,"group_id":21,"created_at":"2014-07-31T15:37:30.000Z","updated_at":"2026-02-26T20:58:45.000Z","published_at":"2014-07-31T15:38:23.000Z","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\u003eIf an array is given as input then find the index of consecutive elements that represent maximum change.\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\u003eExample:\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[ Input    x = [1 10 3 0 2 4 0 -8 9 1]\\n\\n Output   y = [8 9]]]\u003e\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\"}]}"},{"id":2235,"title":"Back to basics - mean of corner elements of a matrix","description":"Calculate the mean of corner elements of a matrix.\r\n\r\ne.g. a=[1 2 3;\r\n        4 5 6;\r\n        7 8 9;]\r\n\r\nMean = (1+3+7+9)/4 = 5","description_html":"\u003cp\u003eCalculate the mean of corner elements of a matrix.\u003c/p\u003e\u003cp\u003ee.g. a=[1 2 3;\r\n        4 5 6;\r\n        7 8 9;]\u003c/p\u003e\u003cp\u003eMean = (1+3+7+9)/4 = 5\u003c/p\u003e","function_template":"function y = MeanCorner(x)\r\n  y = x;\r\nend","test_suite":"%%\r\nx = [1 2 3; 4 5 6; 7 8 9]\r\ny_correct = 5;\r\nassert(isequal(MeanCorner(x),y_correct))\r\n\r\n\r\n%%\r\nx = magic(4)\r\ny_correct = 8.5;\r\nassert(isequal(MeanCorner(x),y_correct))\r\n\r\n\r\n%%\r\nx = eye(4)\r\ny_correct = 0.5;\r\nassert(isequal(MeanCorner(x),y_correct))\r\n\r\n\r\n%%\r\nx = repmat(5, 4,4);\r\ny_correct = 5;\r\nassert(isequal(MeanCorner(x),y_correct))\r\n\r\n%%\r\nx = [1:10];\r\ny_correct = 5.5;\r\nassert(isequal(MeanCorner(x),y_correct))\r\n\r\n\r\n","published":true,"deleted":false,"likes_count":4,"comments_count":0,"created_by":16381,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":463,"test_suite_updated_at":null,"rescore_all_solutions":false,"group_id":21,"created_at":"2014-03-04T20:59:30.000Z","updated_at":"2026-04-08T08:26:57.000Z","published_at":"2014-03-04T21:00:18.000Z","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\u003eCalculate the mean of corner elements of a matrix.\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\u003ee.g. a=[1 2 3; 4 5 6; 7 8 9;]\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\u003eMean = (1+3+7+9)/4 = 5\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\"}]}"},{"id":1985,"title":"How unique?","description":"Sometimes, when we check unique entries of vector we would like to know how many times each value occurs.\r\n\r\nGiven vector of numbers *A* return vector *U* of unique values of A and corresponding vector *H* with occurrences.\r\n\r\nExample:\r\n\r\n   in:  A = [2 2 2 3 3 2 3 8 6 5 6]\r\n  out:  U = [2 3 8 6 5]\r\n        H = [4 3 1 2 1]  ","description_html":"\u003cp\u003eSometimes, when we check unique entries of vector we would like to know how many times each value occurs.\u003c/p\u003e\u003cp\u003eGiven vector of numbers \u003cb\u003eA\u003c/b\u003e return vector \u003cb\u003eU\u003c/b\u003e of unique values of A and corresponding vector \u003cb\u003eH\u003c/b\u003e with occurrences.\u003c/p\u003e\u003cp\u003eExample:\u003c/p\u003e\u003cpre\u003e   in:  A = [2 2 2 3 3 2 3 8 6 5 6]\r\n  out:  U = [2 3 8 6 5]\r\n        H = [4 3 1 2 1]  \u003c/pre\u003e","function_template":"function [U,H] = hunique(A)\r\n  U = 1:5;\r\n  H = ones(1,5);\r\nend","test_suite":"%%\r\nA = [2 2 2 3 3 2 3 8 6 5 6];\r\n[U, H] = hunique(A);\r\nU_ok = [2 3 8 6 5];\r\nH_ok = [4 3 1 2 1];\r\nassert(isequal(U,U_ok));\r\nassert(isequal(H,H_ok));\r\n%%\r\nA = [2 2 2 3 3 2 3 8 6 5 6 8];\r\n[U, H] = hunique(A);\r\nU_ok = [2 3 8 6 5];\r\nH_ok = [4 3 2 2 1];\r\nassert(isequal(U,U_ok));\r\nassert(isequal(H,H_ok));\r\n%%\r\nA = 100:-11:1;\r\nassert(isequal(hunique(A),A));\r\n[~,H] = hunique(A);\r\nassert(isequal(H,ones(1,10)));\r\n%%\r\nA = randi([-10 10],1,100);\r\n[U,H] = hunique(A);\r\nassert(sum(H)==numel(A));\r\nassert(isequal(unique(A),sort(U)));\r\n\r\n% number of test cases may increace in the future.\r\n% any proposals of test cases warmly welcome.","published":true,"deleted":false,"likes_count":1,"comments_count":0,"created_by":14358,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":137,"test_suite_updated_at":"2014-04-06T18:52:22.000Z","rescore_all_solutions":false,"group_id":21,"created_at":"2013-11-12T23:00:10.000Z","updated_at":"2026-02-26T16:00:10.000Z","published_at":"2013-11-13T23:40:01.000Z","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\u003eSometimes, when we check unique entries of vector we would like to know how many times each value occurs.\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\u003eGiven vector of numbers\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e \u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:rPr\u003e\u003cw:b/\u003e\u003c/w:rPr\u003e\u003cw:t\u003eA\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e return vector\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e \u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:rPr\u003e\u003cw:b/\u003e\u003c/w:rPr\u003e\u003cw:t\u003eU\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e of unique values of A and corresponding vector\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e \u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:rPr\u003e\u003cw:b/\u003e\u003c/w:rPr\u003e\u003cw:t\u003eH\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e with occurrences.\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\u003eExample:\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[   in:  A = [2 2 2 3 3 2 3 8 6 5 6]\\n  out:  U = [2 3 8 6 5]\\n        H = [4 3 1 2 1]]]\u003e\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":2145,"title":"Find the index of n in magic(n)","description":"If input n=5, then magic(n) is\r\n\r\n    17    24     1     8    15\r\n    23     5     7    14    16\r\n     4     6    13    20    22\r\n    10    12    19    21     3\r\n    11    18    25     2     9\r\n\r\nThe output is of the form [row,column] for the place where n appears.\r\n\r\n output = [2,2]\r\n","description_html":"\u003cp\u003eIf input n=5, then magic(n) is\u003c/p\u003e\u003cpre\u003e    17    24     1     8    15\r\n    23     5     7    14    16\r\n     4     6    13    20    22\r\n    10    12    19    21     3\r\n    11    18    25     2     9\u003c/pre\u003e\u003cp\u003eThe output is of the form [row,column] for the place where n appears.\u003c/p\u003e\u003cpre\u003e output = [2,2]\u003c/pre\u003e","function_template":"function y = nim(x)\r\n  y = x;\r\nend","test_suite":"%%\r\nx = 7;\r\ny_correct = [2,3];\r\nassert(isequal(nim(x),y_correct))\r\n%%\r\nx = 11;\r\ny_correct = [2,5];\r\nassert(isequal(nim(x),y_correct))\r\n%%\r\nx = 3;\r\ny_correct = [2,1];\r\nassert(isequal(nim(x),y_correct))","published":true,"deleted":false,"likes_count":5,"comments_count":1,"created_by":1690,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":273,"test_suite_updated_at":null,"rescore_all_solutions":false,"group_id":21,"created_at":"2014-01-31T07:51:37.000Z","updated_at":"2026-04-01T20:58:17.000Z","published_at":"2014-01-31T07:51:37.000Z","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\u003eIf input n=5, then magic(n) is\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[    17    24     1     8    15\\n    23     5     7    14    16\\n     4     6    13    20    22\\n    10    12    19    21     3\\n    11    18    25     2     9]]\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 output is of the form [row,column] for the place where n appears.\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[ output = [2,2]]]\u003e\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\"}]}"},{"id":1923,"title":"Find the maximum two numbers of every column of a matrix","description":"Find the maximum two numbers of every column of a matrix.\r\n\r\nExample:\r\n\r\nIf we input a matrix \r\n\r\n A = [ 1 2 4\r\n       6 0 3\r\n       4 1 5 ]\r\n\r\nwe should get\r\n\r\n B = [ 6 2 5\r\n       4 1 4 ]\r\n","description_html":"\u003cp\u003eFind the maximum two numbers of every column of a matrix.\u003c/p\u003e\u003cp\u003eExample:\u003c/p\u003e\u003cp\u003eIf we input a matrix\u003c/p\u003e\u003cpre\u003e A = [ 1 2 4\r\n       6 0 3\r\n       4 1 5 ]\u003c/pre\u003e\u003cp\u003ewe should get\u003c/p\u003e\u003cpre\u003e B = [ 6 2 5\r\n       4 1 4 ]\u003c/pre\u003e","function_template":"function y = your_fcn_name(x)\r\n  y = x;\r\nend","test_suite":"%%\r\nx = [1 2 4;\r\n     6 0 3;\r\n     4 1 5];\r\ny_correct = [6 2 5;\r\n             4 1 4];\r\nassert(isequal(your_fcn_name(x),y_correct))\r\n\r\n%%\r\nx = ones(3);\r\ny_correct = ones(2,3);\r\nassert(isequal(your_fcn_name(x),y_correct))\r\n\r\n%%\r\nx = eye(4);\r\ny_correct = [ones(1,4); zeros(1,4)];\r\nassert(isequal(your_fcn_name(x),y_correct))\r\n\r\n%%\r\nx = [1:5;\r\n     6:10;\r\n     11:15;\r\n     16:20;\r\n     21:25];\r\ny_correct = [21:25; 16:20];\r\nassert(isequal(your_fcn_name(x),y_correct))\r\n\r\n%%\r\nx = [1 5 7 3 47 2  3;\r\n     6 7 1 5 23 1 47;\r\n     7 1 3 2 68 4 11];\r\ny_correct = [7 7 7 5 68 4 47;\r\n             6 5 3 3 47 2 11];\r\nassert(isequal(your_fcn_name(x),y_correct))","published":true,"deleted":false,"likes_count":1,"comments_count":1,"created_by":3668,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":231,"test_suite_updated_at":"2017-03-15T16:43:08.000Z","rescore_all_solutions":false,"group_id":21,"created_at":"2013-10-08T14:30:23.000Z","updated_at":"2026-03-31T17:07:39.000Z","published_at":"2013-10-08T14:30:22.000Z","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\u003eFind the maximum two numbers of every column of a matrix.\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\u003eExample:\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 we input a matrix\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[ A = [ 1 2 4\\n       6 0 3\\n       4 1 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\u003ewe should get\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[ B = [ 6 2 5\\n       4 1 4 ]]]\u003e\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\"}]}"},{"id":2476,"title":"Max Change in Consecutive Elements","description":"If an array is given as input then find the index of consecutive elements that represent maximum change.\r\n\r\nExample:\r\n\r\n Input    x = [1 10 3 0 2 4 0 -8 9 1]\r\n\r\n Output   y = [8 9]","description_html":"\u003cp\u003eIf an array is given as input then find the index of consecutive elements that represent maximum change.\u003c/p\u003e\u003cp\u003eExample:\u003c/p\u003e\u003cpre\u003e Input    x = [1 10 3 0 2 4 0 -8 9 1]\u003c/pre\u003e\u003cpre\u003e Output   y = [8 9]\u003c/pre\u003e","function_template":"function y = maxChange(x)\r\n  y = x;\r\nend","test_suite":"%%\r\nx = [1 10 3 0 2 4 0 -8 9 1];\r\ny_correct = [8 9];\r\nassert(isequal(maxChange(x),y_correct))\r\n\r\n%%\r\nx = [10 15 2 18 40];\r\ny_correct = [4 5];\r\nassert(isequal(maxChange(x),y_correct))\r\n\r\n%%\r\nx = 1:10;\r\nx(4) = 0;\r\ny_correct = [4 5];\r\nassert(isequal(maxChange(x),y_correct))\r\n\r\n%%\r\nx = [1 10 100 1e3 1e4 1e5 1e6 1e7];\r\ny_correct = [7 8];\r\nassert(isequal(maxChange(x),y_correct))\r\n\r\n%%\r\nx = [-10 10 -8 7 -5 3 -2 1 -1 0];\r\ny_correct = [1 2];\r\nassert(isequal(maxChange(x),y_correct))\r\n\r\n%%\r\nx = ones(1,1e6);\r\nx(789) = 0; x(788) = 0.5;\r\ny_correct = [789 790];\r\nassert(isequal(maxChange(x),y_correct))","published":true,"deleted":false,"likes_count":3,"comments_count":6,"created_by":16361,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":181,"test_suite_updated_at":"2017-03-15T17:18:53.000Z","rescore_all_solutions":false,"group_id":21,"created_at":"2014-07-31T15:37:30.000Z","updated_at":"2026-02-26T20:58:45.000Z","published_at":"2014-07-31T15:38:23.000Z","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\u003eIf an array is given as input then find the index of consecutive elements that represent maximum change.\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\u003eExample:\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[ Input    x = [1 10 3 0 2 4 0 -8 9 1]\\n\\n Output   y = [8 9]]]\u003e\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\"}]}"},{"id":2235,"title":"Back to basics - mean of corner elements of a matrix","description":"Calculate the mean of corner elements of a matrix.\r\n\r\ne.g. a=[1 2 3;\r\n        4 5 6;\r\n        7 8 9;]\r\n\r\nMean = (1+3+7+9)/4 = 5","description_html":"\u003cp\u003eCalculate the mean of corner elements of a matrix.\u003c/p\u003e\u003cp\u003ee.g. a=[1 2 3;\r\n        4 5 6;\r\n        7 8 9;]\u003c/p\u003e\u003cp\u003eMean = (1+3+7+9)/4 = 5\u003c/p\u003e","function_template":"function y = MeanCorner(x)\r\n  y = x;\r\nend","test_suite":"%%\r\nx = [1 2 3; 4 5 6; 7 8 9]\r\ny_correct = 5;\r\nassert(isequal(MeanCorner(x),y_correct))\r\n\r\n\r\n%%\r\nx = magic(4)\r\ny_correct = 8.5;\r\nassert(isequal(MeanCorner(x),y_correct))\r\n\r\n\r\n%%\r\nx = eye(4)\r\ny_correct = 0.5;\r\nassert(isequal(MeanCorner(x),y_correct))\r\n\r\n\r\n%%\r\nx = repmat(5, 4,4);\r\ny_correct = 5;\r\nassert(isequal(MeanCorner(x),y_correct))\r\n\r\n%%\r\nx = [1:10];\r\ny_correct = 5.5;\r\nassert(isequal(MeanCorner(x),y_correct))\r\n\r\n\r\n","published":true,"deleted":false,"likes_count":4,"comments_count":0,"created_by":16381,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":463,"test_suite_updated_at":null,"rescore_all_solutions":false,"group_id":21,"created_at":"2014-03-04T20:59:30.000Z","updated_at":"2026-04-08T08:26:57.000Z","published_at":"2014-03-04T21:00:18.000Z","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\u003eCalculate the mean of corner elements of a matrix.\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\u003ee.g. a=[1 2 3; 4 5 6; 7 8 9;]\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\u003eMean = (1+3+7+9)/4 = 5\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\\\" 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hunique(A);\r\nassert(sum(H)==numel(A));\r\nassert(isequal(unique(A),sort(U)));\r\n\r\n% number of test cases may increace in the future.\r\n% any proposals of test cases warmly welcome.","published":true,"deleted":false,"likes_count":1,"comments_count":0,"created_by":14358,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":137,"test_suite_updated_at":"2014-04-06T18:52:22.000Z","rescore_all_solutions":false,"group_id":21,"created_at":"2013-11-12T23:00:10.000Z","updated_at":"2026-02-26T16:00:10.000Z","published_at":"2013-11-13T23:40:01.000Z","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 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