{"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":45199,"title":"Quadratic equation ","description":"given three inputs (a, b, c) for the equation a*x^2+b*x+c=0; return 1 if the roots are complex (non zero imaginary), and 0 if they are real.","description_html":"\u003cp\u003egiven three inputs (a, b, c) for the equation a*x^2+b*x+c=0; return 1 if the roots are complex (non zero imaginary), and 0 if they are real.\u003c/p\u003e","function_template":"function y = your_fcn_name(a,b,c)\r\n  y = 1;\r\nend","test_suite":"%%\r\na=1;\r\nb=-1;\r\nc=1;\r\ny_correct = 1;\r\nassert(isequal(your_fcn_name(a,b,c),y_correct))\r\n\r\n%%\r\na=1;\r\nb=0;\r\nc=0;\r\ny_correct = 0;\r\nassert(isequal(your_fcn_name(a,b,c),y_correct))\r\n\r\n%%\r\na=1;\r\nb=-1;\r\nc=-2;\r\ny_correct = 0;\r\nassert(isequal(your_fcn_name(a,b,c),y_correct))\r\n\r\n\r\n","published":true,"deleted":false,"likes_count":0,"comments_count":0,"created_by":366963,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":80,"test_suite_updated_at":"2019-11-08T16:59:36.000Z","rescore_all_solutions":false,"group_id":1,"created_at":"2019-11-08T16:46:45.000Z","updated_at":"2026-03-10T15:16:43.000Z","published_at":"2019-11-08T16:55:49.000Z","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\u003egiven three inputs (a, b, c) for the equation a*x^2+b*x+c=0; return 1 if the roots are complex (non zero imaginary), and 0 if they are real.\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":42988,"title":"Linear system of equations","description":"Solve the system of equations in three variables.","description_html":"\u003cp\u003eSolve the system of equations in three variables.\u003c/p\u003e","function_template":"function y = lin_eqns(A,b)\r\n  y = b;\r\nend","test_suite":"%%\r\nA=[1 1 1;2 4 8;3 9 27];\r\nb=[1;2;3];\r\ny_correct = [1;0;0];\r\ntol = 1e-14;\r\nassert(norm(lin_eqns(A,b)-y_correct) \u003c tol)\r\n\r\n%%\r\nA=[2 1 -2;1 -1 -1;1 1 3];\r\nb=[3;0;12];\r\ny_correct = [3.5;1;2.5];\r\ntol = 1e-14;\r\nassert(norm(lin_eqns(A,b)-y_correct) \u003c tol)\r\n\r\n%%\r\nA=[1 0 0;0 1 0;0 0 1];\r\nb=[1e6;1e7;1e8];\r\ny_correct = [1e6;1e7;1e8];\r\ntol = 1e-9;\r\nassert(norm(lin_eqns(A,b)-y_correct) \u003c tol)\r\n\r\n%%\r\nA=[1 0 1;0 -3 1;2 1 3];\r\nb=[6;7;15];\r\ny_correct = [2;-1;4];\r\ntol = 1e-14;\r\nassert(norm(lin_eqns(A,b)-y_correct) \u003c tol)\r\n","published":true,"deleted":false,"likes_count":13,"comments_count":1,"created_by":91311,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":468,"test_suite_updated_at":"2016-10-02T01:16:37.000Z","rescore_all_solutions":true,"group_id":1,"created_at":"2016-09-19T10:00:24.000Z","updated_at":"2026-03-29T20:48:31.000Z","published_at":"2016-09-19T10:00:24.000Z","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\",\"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\u003eSolve the system of equations in three variables.\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":43590,"title":"Solve t^(a*x^2+b*x+c)=s","description":"Solve t^(a*x^2+b*x+c)=s. Return x vector as result.\r\n\r\nExample a=1, b=2, c=1, t=3, s=15. Result x(1)= 0.5700  x(2)=-2.5700 \r\n\r\nHint: if we need to solve a*x^2+b*x+c=0 then result will be\r\n\r\nx(1)=(-b+sqrt(b^2-4*a*c))/(2*a); \r\n\r\nx(2)=(-b-sqrt(b^2-4*a*c))/(2*a); ","description_html":"\u003cp\u003eSolve t^(a*x^2+b*x+c)=s. Return x vector as result.\u003c/p\u003e\u003cp\u003eExample a=1, b=2, c=1, t=3, s=15. Result x(1)= 0.5700  x(2)=-2.5700\u003c/p\u003e\u003cp\u003eHint: if we need to solve a*x^2+b*x+c=0 then result will be\u003c/p\u003e\u003cp\u003ex(1)=(-b+sqrt(b^2-4*a*c))/(2*a);\u003c/p\u003e\u003cp\u003ex(2)=(-b-sqrt(b^2-4*a*c))/(2*a);\u003c/p\u003e","function_template":"function x = SolveEquation(a,b,c,t,s)\r\n  y = x;\r\nend","test_suite":"%%\r\na=1;\r\nb=2;\r\nc=1;\r\nt=3;\r\ns=15;\r\ny=SolveEquation(a,b,c,t,s)\r\ny_correct = [ 0.5700  , -2.5700]\r\ntolerance = 1e-4; \r\nassert(abs(y(1)-y_correct(1))\u003ctolerance)\r\nassert(abs(y(2)-y_correct(2))\u003ctolerance)\r\n%%\r\na=1;\r\nb=2;\r\nc=2;\r\nt=exp(1);\r\ns=exp(1);\r\ny=SolveEquation(a,b,c,t,s)\r\ny_correct = [ -1 , -1]\r\ntolerance = 1e-4; \r\nassert(abs(y(1)-y_correct(1))\u003ctolerance)\r\nassert(abs(y(2)-y_correct(2))\u003ctolerance)\r\n","published":true,"deleted":false,"likes_count":2,"comments_count":2,"created_by":90467,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":63,"test_suite_updated_at":null,"rescore_all_solutions":false,"group_id":1,"created_at":"2016-10-22T17:32:46.000Z","updated_at":"2026-03-30T13:39:19.000Z","published_at":"2016-10-22T17:32:46.000Z","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\u003eSolve t^(a*x^2+b*x+c)=s. Return x vector as result.\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\u003eExample a=1, b=2, c=1, t=3, s=15. Result x(1)= 0.5700 x(2)=-2.5700\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\u003eHint: if we need to solve a*x^2+b*x+c=0 then result will be\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\u003ex(1)=(-b+sqrt(b^2-4*a*c))/(2*a);\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\u003ex(2)=(-b-sqrt(b^2-4*a*c))/(2*a);\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":44037,"title":"Pascal's triangle","description":"\u003chttps://en.wikipedia.org/wiki/Pascal%27s_triangle\u003e\r\nif the order is: x = 3; the output will be:\r\n\r\n\r\n    output = [0 0 0 1 0 0 0;\r\n              0 0 1 0 1 0 0;\r\n              0 1 0 2 0 1 0;\r\n              1 0 3 0 3 0 1]","description_html":"\u003cp\u003e\u003ca href = \"https://en.wikipedia.org/wiki/Pascal%27s_triangle\"\u003ehttps://en.wikipedia.org/wiki/Pascal%27s_triangle\u003c/a\u003e\r\nif the order is: x = 3; the output will be:\u003c/p\u003e\u003cpre\u003e    output = [0 0 0 1 0 0 0;\r\n              0 0 1 0 1 0 0;\r\n              0 1 0 2 0 1 0;\r\n              1 0 3 0 3 0 1]\u003c/pre\u003e","function_template":"function y = stg_Pascal(x)\r\n  y = [];\r\nend","test_suite":"%%\r\nx = 3;\r\ny_correct =  [0 0 0 1 0 0 0;\r\n              0 0 1 0 1 0 0;\r\n              0 1 0 2 0 1 0;\r\n              1 0 3 0 3 0 1];\r\nassert(isequal(stg_Pascal(x),y_correct))\r\n\r\n%%\r\nx = 4;\r\ny_correct =  [0 0 0 0 1 0 0 0 0;\r\n              0 0 0 1 0 1 0 0 0;\r\n              0 0 1 0 2 0 1 0 0;\r\n              0 1 0 3 0 3 0 1 0;\r\n              1 0 4 0 6 0 4 0 1];\r\nassert(isequal(stg_Pascal(x),y_correct))\r\n\r\n%%\r\nx = 2;\r\ny_correct =  [0 0 1 0 0;\r\n              0 1 0 1 0;\r\n              1 0 2 0 1];\r\nassert(isequal(stg_Pascal(x),y_correct))","published":true,"deleted":false,"likes_count":2,"comments_count":0,"created_by":108804,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":38,"test_suite_updated_at":null,"rescore_all_solutions":false,"group_id":1,"created_at":"2017-01-23T15:05:29.000Z","updated_at":"2026-03-14T18:48:45.000Z","published_at":"2017-01-23T15:05:29.000Z","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:hyperlink w:docLocation=\\\"https://en.wikipedia.org/wiki/Pascal%27s_triangle\\\"\u003e\u003cw:r\u003e\u003cw:t\u003e\u0026lt;https://en.wikipedia.org/wiki/Pascal%27s_triangle\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:hyperlink\u003e\u003cw:r\u003e\u003cw:t\u003e\u0026gt; if the order is: x = 3; the output will 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[    output = [0 0 0 1 0 0 0;\\n              0 0 1 0 1 0 0;\\n              0 1 0 2 0 1 0;\\n              1 0 3 0 3 0 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":45199,"title":"Quadratic equation ","description":"given three inputs (a, b, c) for the equation a*x^2+b*x+c=0; return 1 if the roots are complex (non zero imaginary), and 0 if they are real.","description_html":"\u003cp\u003egiven three inputs (a, b, c) for the equation a*x^2+b*x+c=0; return 1 if the roots are complex (non zero imaginary), and 0 if they are real.\u003c/p\u003e","function_template":"function y = your_fcn_name(a,b,c)\r\n  y = 1;\r\nend","test_suite":"%%\r\na=1;\r\nb=-1;\r\nc=1;\r\ny_correct = 1;\r\nassert(isequal(your_fcn_name(a,b,c),y_correct))\r\n\r\n%%\r\na=1;\r\nb=0;\r\nc=0;\r\ny_correct = 0;\r\nassert(isequal(your_fcn_name(a,b,c),y_correct))\r\n\r\n%%\r\na=1;\r\nb=-1;\r\nc=-2;\r\ny_correct = 0;\r\nassert(isequal(your_fcn_name(a,b,c),y_correct))\r\n\r\n\r\n","published":true,"deleted":false,"likes_count":0,"comments_count":0,"created_by":366963,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":80,"test_suite_updated_at":"2019-11-08T16:59:36.000Z","rescore_all_solutions":false,"group_id":1,"created_at":"2019-11-08T16:46:45.000Z","updated_at":"2026-03-10T15:16:43.000Z","published_at":"2019-11-08T16:55:49.000Z","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\u003egiven three inputs (a, b, c) for the equation a*x^2+b*x+c=0; return 1 if the roots are complex (non zero imaginary), and 0 if they are real.\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":42988,"title":"Linear system of equations","description":"Solve the system of equations in three variables.","description_html":"\u003cp\u003eSolve the system of equations in three variables.\u003c/p\u003e","function_template":"function y = lin_eqns(A,b)\r\n  y = b;\r\nend","test_suite":"%%\r\nA=[1 1 1;2 4 8;3 9 27];\r\nb=[1;2;3];\r\ny_correct = [1;0;0];\r\ntol = 1e-14;\r\nassert(norm(lin_eqns(A,b)-y_correct) \u003c tol)\r\n\r\n%%\r\nA=[2 1 -2;1 -1 -1;1 1 3];\r\nb=[3;0;12];\r\ny_correct = [3.5;1;2.5];\r\ntol = 1e-14;\r\nassert(norm(lin_eqns(A,b)-y_correct) \u003c tol)\r\n\r\n%%\r\nA=[1 0 0;0 1 0;0 0 1];\r\nb=[1e6;1e7;1e8];\r\ny_correct = [1e6;1e7;1e8];\r\ntol = 1e-9;\r\nassert(norm(lin_eqns(A,b)-y_correct) \u003c tol)\r\n\r\n%%\r\nA=[1 0 1;0 -3 1;2 1 3];\r\nb=[6;7;15];\r\ny_correct = [2;-1;4];\r\ntol = 1e-14;\r\nassert(norm(lin_eqns(A,b)-y_correct) \u003c tol)\r\n","published":true,"deleted":false,"likes_count":13,"comments_count":1,"created_by":91311,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":468,"test_suite_updated_at":"2016-10-02T01:16:37.000Z","rescore_all_solutions":true,"group_id":1,"created_at":"2016-09-19T10:00:24.000Z","updated_at":"2026-03-29T20:48:31.000Z","published_at":"2016-09-19T10:00:24.000Z","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\",\"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\u003eSolve the system of equations in three variables.\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":43590,"title":"Solve t^(a*x^2+b*x+c)=s","description":"Solve t^(a*x^2+b*x+c)=s. Return x vector as result.\r\n\r\nExample a=1, b=2, c=1, t=3, s=15. Result x(1)= 0.5700  x(2)=-2.5700 \r\n\r\nHint: if we need to solve a*x^2+b*x+c=0 then result will be\r\n\r\nx(1)=(-b+sqrt(b^2-4*a*c))/(2*a); \r\n\r\nx(2)=(-b-sqrt(b^2-4*a*c))/(2*a); ","description_html":"\u003cp\u003eSolve t^(a*x^2+b*x+c)=s. Return x vector as result.\u003c/p\u003e\u003cp\u003eExample a=1, b=2, c=1, t=3, s=15. Result x(1)= 0.5700  x(2)=-2.5700\u003c/p\u003e\u003cp\u003eHint: if we need to solve a*x^2+b*x+c=0 then result will be\u003c/p\u003e\u003cp\u003ex(1)=(-b+sqrt(b^2-4*a*c))/(2*a);\u003c/p\u003e\u003cp\u003ex(2)=(-b-sqrt(b^2-4*a*c))/(2*a);\u003c/p\u003e","function_template":"function x = SolveEquation(a,b,c,t,s)\r\n  y = x;\r\nend","test_suite":"%%\r\na=1;\r\nb=2;\r\nc=1;\r\nt=3;\r\ns=15;\r\ny=SolveEquation(a,b,c,t,s)\r\ny_correct = [ 0.5700  , -2.5700]\r\ntolerance = 1e-4; \r\nassert(abs(y(1)-y_correct(1))\u003ctolerance)\r\nassert(abs(y(2)-y_correct(2))\u003ctolerance)\r\n%%\r\na=1;\r\nb=2;\r\nc=2;\r\nt=exp(1);\r\ns=exp(1);\r\ny=SolveEquation(a,b,c,t,s)\r\ny_correct = [ -1 , -1]\r\ntolerance = 1e-4; \r\nassert(abs(y(1)-y_correct(1))\u003ctolerance)\r\nassert(abs(y(2)-y_correct(2))\u003ctolerance)\r\n","published":true,"deleted":false,"likes_count":2,"comments_count":2,"created_by":90467,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":63,"test_suite_updated_at":null,"rescore_all_solutions":false,"group_id":1,"created_at":"2016-10-22T17:32:46.000Z","updated_at":"2026-03-30T13:39:19.000Z","published_at":"2016-10-22T17:32:46.000Z","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\u003eSolve t^(a*x^2+b*x+c)=s. Return x vector as result.\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\u003eExample a=1, b=2, c=1, t=3, s=15. Result x(1)= 0.5700 x(2)=-2.5700\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\u003eHint: if we need to solve a*x^2+b*x+c=0 then result will be\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\u003ex(1)=(-b+sqrt(b^2-4*a*c))/(2*a);\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\u003ex(2)=(-b-sqrt(b^2-4*a*c))/(2*a);\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":44037,"title":"Pascal's triangle","description":"\u003chttps://en.wikipedia.org/wiki/Pascal%27s_triangle\u003e\r\nif the order is: x = 3; the output will be:\r\n\r\n\r\n    output = [0 0 0 1 0 0 0;\r\n              0 0 1 0 1 0 0;\r\n              0 1 0 2 0 1 0;\r\n              1 0 3 0 3 0 1]","description_html":"\u003cp\u003e\u003ca href = \"https://en.wikipedia.org/wiki/Pascal%27s_triangle\"\u003ehttps://en.wikipedia.org/wiki/Pascal%27s_triangle\u003c/a\u003e\r\nif the order is: x = 3; the output will be:\u003c/p\u003e\u003cpre\u003e    output = [0 0 0 1 0 0 0;\r\n              0 0 1 0 1 0 0;\r\n              0 1 0 2 0 1 0;\r\n              1 0 3 0 3 0 1]\u003c/pre\u003e","function_template":"function y = stg_Pascal(x)\r\n  y = [];\r\nend","test_suite":"%%\r\nx = 3;\r\ny_correct =  [0 0 0 1 0 0 0;\r\n              0 0 1 0 1 0 0;\r\n              0 1 0 2 0 1 0;\r\n              1 0 3 0 3 0 1];\r\nassert(isequal(stg_Pascal(x),y_correct))\r\n\r\n%%\r\nx = 4;\r\ny_correct =  [0 0 0 0 1 0 0 0 0;\r\n              0 0 0 1 0 1 0 0 0;\r\n              0 0 1 0 2 0 1 0 0;\r\n              0 1 0 3 0 3 0 1 0;\r\n              1 0 4 0 6 0 4 0 1];\r\nassert(isequal(stg_Pascal(x),y_correct))\r\n\r\n%%\r\nx = 2;\r\ny_correct =  [0 0 1 0 0;\r\n              0 1 0 1 0;\r\n              1 0 2 0 1];\r\nassert(isequal(stg_Pascal(x),y_correct))","published":true,"deleted":false,"likes_count":2,"comments_count":0,"created_by":108804,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":38,"test_suite_updated_at":null,"rescore_all_solutions":false,"group_id":1,"created_at":"2017-01-23T15:05:29.000Z","updated_at":"2026-03-14T18:48:45.000Z","published_at":"2017-01-23T15:05:29.000Z","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:hyperlink w:docLocation=\\\"https://en.wikipedia.org/wiki/Pascal%27s_triangle\\\"\u003e\u003cw:r\u003e\u003cw:t\u003e\u0026lt;https://en.wikipedia.org/wiki/Pascal%27s_triangle\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:hyperlink\u003e\u003cw:r\u003e\u003cw:t\u003e\u0026gt; if the order is: x = 3; the output will 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[    output = [0 0 0 1 0 0 0;\\n              0 0 1 0 1 0 0;\\n              0 1 0 2 0 1 0;\\n              1 0 3 0 3 0 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 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