{"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":43298,"title":"Calculate area of sector","description":"A=function(r,seta)\r\n\r\nr is radius of sector, seta is angle of sector, and A is its area. Area of sector A is defined as 0.5*(r^2)*seta;","description_html":"\u003cdiv style = \"text-align: start; line-height: 20.44px; min-height: 0px; white-space: normal; color: rgb(0, 0, 0); font-family: Menlo, Monaco, Consolas, monospace; font-style: normal; font-size: 14px; font-weight: 400; text-decoration: none solid rgb(0, 0, 0); white-space: normal; \"\u003e\u003cdiv style=\"block-size: 51px; display: block; min-width: 0px; padding-block-start: 0px; padding-top: 0px; perspective-origin: 407px 25.5px; transform-origin: 407px 25.5px; vertical-align: baseline; \"\u003e\u003cdiv style=\"block-size: 21px; font-family: Helvetica, Arial, sans-serif; line-height: 21px; margin-block-end: 9px; margin-block-start: 2px; margin-bottom: 9px; margin-inline-end: 10px; margin-inline-start: 4px; margin-left: 4px; margin-right: 10px; margin-top: 2px; perspective-origin: 384px 10.5px; text-align: left; transform-origin: 384px 10.5px; white-space: pre-wrap; margin-left: 4px; margin-top: 2px; margin-bottom: 9px; margin-right: 10px; \"\u003e\u003cspan style=\"block-size: auto; display: inline; margin-block-end: 0px; margin-block-start: 0px; margin-bottom: 0px; margin-inline-end: 0px; margin-inline-start: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; perspective-origin: 0px 0px; transform-origin: 0px 0px; \"\u003e\u003cspan style=\"\"\u003eA=function(r,seta)\u003c/span\u003e\u003c/span\u003e\u003c/div\u003e\u003cdiv style=\"block-size: 21px; font-family: Helvetica, Arial, sans-serif; line-height: 21px; margin-block-end: 9px; margin-block-start: 2px; margin-bottom: 9px; margin-inline-end: 10px; margin-inline-start: 4px; margin-left: 4px; margin-right: 10px; margin-top: 2px; perspective-origin: 384px 10.5px; text-align: left; transform-origin: 384px 10.5px; white-space: pre-wrap; margin-left: 4px; margin-top: 2px; margin-bottom: 9px; margin-right: 10px; \"\u003e\u003cspan style=\"block-size: auto; display: inline; margin-block-end: 0px; margin-block-start: 0px; margin-bottom: 0px; margin-inline-end: 0px; margin-inline-start: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; perspective-origin: 0px 0px; transform-origin: 0px 0px; \"\u003e\u003cspan style=\"\"\u003er(m) is radius of sector, seta (radian) is angle of sector, and A (m^2) is its area.\u003c/span\u003e\u003c/span\u003e\u003c/div\u003e\u003c/div\u003e\u003c/div\u003e","function_template":"function y = sectorarea(r,seta)\r\n  y =\r\nend","test_suite":"%%\r\nr=1\r\nseta=pi/2\r\ny_correct = 0.7854;\r\nassert(abs(sectorarea(r,seta)-y_correct)\u003c0.001)\r\n\r\n%%\r\nr=2\r\nseta=pi/2\r\ny_correct = pi;\r\nassert(abs(sectorarea(r,seta)-y_correct)\u003c0.001)\r\n\r\n%%\r\nr=sqrt(2);\r\nseta=pi/3\r\ny_correct = pi/3;\r\nassert(abs(sectorarea(r,seta)-y_correct)\u003c0.001)\r\n\r\n%%\r\nr= 6\r\nseta=pi/6;\r\ny_correct = 3*pi;\r\nassert(abs(sectorarea(r,seta)-y_correct)\u003c0.001)\r\n\r\n%%\r\nr= pi\r\nseta= pi\r\ny_correct = 0.5*pi^3;\r\nassert(abs(sectorarea(r,seta)-y_correct)\u003c0.001)\r\n","published":true,"deleted":false,"likes_count":21,"comments_count":6,"created_by":33533,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":3480,"test_suite_updated_at":"2021-02-21T07:46:40.000Z","rescore_all_solutions":true,"group_id":1,"created_at":"2016-10-10T09:02:12.000Z","updated_at":"2026-04-17T02:07:35.000Z","published_at":"2016-10-10T09:02:12.000Z","restored_at":null,"restored_by":null,"spam":false,"simulink":false,"admin_reviewed":false,"description_opc":"{\"parts\":[{\"partUri\":\"/matlab/document.xml\",\"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\u003cw:jc w:val=\\\"left\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eA=function(r,seta)\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\u003er(m) is radius of sector, seta (radian) is angle of sector, and A (m^2) is its area.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003c/w:body\u003e\u003c/w:document\u003e\",\"relationship\":null}],\"relationships\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/document\",\"target\":\"/matlab/document.xml\",\"relationshipId\":\"rId1\"}]}"},{"id":44273,"title":"Given a square and a circle, please decide whether the square covers more area.","description":"You know the side of a square and the diameter of a circle, please decide whether the square covers more area.","description_html":"\u003cp\u003eYou know the side of a square and the diameter of a circle, please decide whether the square covers more area.\u003c/p\u003e","function_template":"function y = sqci(sq,ci)\r\n  y = (sq\u003eci);\r\nend","test_suite":"%%\r\nsq = 2;\r\nci = 1;\r\ny_correct = (sq\u003eci);\r\nassert(isequal(sqci(sq,ci),y_correct))\r\n\r\n%%\r\nsq = rand;\r\nci = rand;\r\ny_correct = (4*sq^2\u003epi*ci^2);\r\nassert(isequal(sqci(sq,ci),y_correct))\r\n\r\n%%\r\nsq = 0;\r\nci = 0;\r\ny_correct = (0\u003e0);\r\nassert(isequal(sqci(sq,ci),y_correct))\r\n\r\n%%\r\nsq = 100;\r\nci = 4;\r\ny_correct = (7\u003e3);\r\nassert(isequal(sqci(sq,ci),y_correct))\r\n\r\n%%\r\nsq = 21;\r\nci = 127;\r\ny_correct = (3\u003e7);\r\nassert(isequal(sqci(sq,ci),y_correct))\r\n","published":true,"deleted":false,"likes_count":8,"comments_count":3,"created_by":166,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":1747,"test_suite_updated_at":"2017-08-06T18:26:25.000Z","rescore_all_solutions":false,"group_id":1,"created_at":"2017-08-02T14:15:00.000Z","updated_at":"2026-04-17T02:28:23.000Z","published_at":"2017-08-02T14:15:06.000Z","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\u003eYou know the side of a square and the diameter of a circle, please decide whether the square covers more area.\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":954,"title":"Pi Estimate 2","description":"Estimate Pi as described in the following link: http://www.people.virginia.edu/~teh1m/cody/Pi_estimation2.pdf","description_html":"\u003cdiv style = \"text-align: start; line-height: 20.4333px; min-height: 0px; white-space: normal; color: rgb(0, 0, 0); font-family: Menlo, Monaco, Consolas, monospace; font-style: normal; font-size: 14px; font-weight: 400; text-decoration: rgb(0, 0, 0); white-space: normal; \"\u003e\u003cdiv style=\"block-size: 21px; display: block; min-width: 0px; padding-block-start: 0px; padding-top: 0px; perspective-origin: 407px 10.5px; transform-origin: 407px 10.5px; vertical-align: baseline; \"\u003e\u003cdiv style=\"font-family: Helvetica, Arial, sans-serif; line-height: 21px; margin-block-end: 9px; margin-block-start: 2px; margin-bottom: 9px; margin-inline-end: 10px; margin-inline-start: 4px; margin-left: 4px; margin-right: 10px; margin-top: 2px; perspective-origin: 384px 10.5px; text-align: left; transform-origin: 384px 10.5px; white-space: pre-wrap; margin-left: 4px; margin-top: 2px; margin-bottom: 9px; margin-right: 10px; \"\u003e\u003cspan style=\"block-size: auto; display: inline; margin-block-end: 0px; margin-block-start: 0px; margin-bottom: 0px; margin-inline-end: 0px; margin-inline-start: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; perspective-origin: 140.5px 8px; transform-origin: 140.5px 8px; unicode-bidi: normal; \"\u003e\u003cspan style=\"\"\u003eEstimate Pi as described in the following link:\u003c/span\u003e\u003c/span\u003e\u003cspan style=\"block-size: auto; display: inline; margin-block-end: 0px; margin-block-start: 0px; margin-bottom: 0px; margin-inline-end: 0px; margin-inline-start: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; perspective-origin: 2px 8px; transform-origin: 2px 8px; unicode-bidi: normal; \"\u003e\u003cspan style=\"\"\u003e \u003c/span\u003e\u003c/span\u003e\u003ca target='_blank' href = \"/#null\"\u003e\u003cspan style=\"\"\u003e\u003cspan style=\"\"\u003ehttp://www.people.virginia.edu/~teh1m/cody/Pi_estimation2.pdf\u003c/span\u003e\u003c/span\u003e\u003c/a\u003e\u003c/div\u003e\u003c/div\u003e\u003c/div\u003e","function_template":"function [output] = pi_est2(d)\r\n  n=d;\r\n  estimate=d;\r\n  output = [ n  estimate]\r\nend","test_suite":"%%\r\nfiletext = fileread('pi_est2.m');\r\nillegal = contains(filetext, 'str2num') ||  contains(filetext, 'switch'); \r\nassert(~illegal)\r\n\r\n%%\r\nx = 6;\r\ny_correct = [11  3.141592442800000];\r\nassert(isequal(pi_est2(x),y_correct))\r\n%%\r\nx = 4;\r\ny_correct = [8 3.141577086000000];\r\nassert(isequal(pi_est2(x),y_correct))\r\n%%\r\nx = 8;\r\ny_correct = [14 3.141592650600000];\r\nassert(isequal(pi_est2(x),y_correct))\r\n","published":true,"deleted":false,"likes_count":1,"comments_count":10,"created_by":2640,"edited_by":223089,"edited_at":"2022-10-11T11:17:31.000Z","deleted_by":null,"deleted_at":null,"solvers_count":48,"test_suite_updated_at":"2022-10-11T11:17:31.000Z","rescore_all_solutions":false,"group_id":1,"created_at":"2012-09-22T21:49:49.000Z","updated_at":"2026-01-08T21:53:05.000Z","published_at":"2012-09-23T15:59:23.000Z","restored_at":null,"restored_by":null,"spam":null,"simulink":false,"admin_reviewed":false,"description_opc":"{\"parts\":[{\"partUri\":\"/matlab/document.xml\",\"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\u003cw:jc w:val=\\\"left\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eEstimate Pi as described in the following link:\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=\\\"\\\"\u003e\u003cw:r\u003e\u003cw:t\u003ehttp://www.people.virginia.edu/~teh1m/cody/Pi_estimation2.pdf\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:hyperlink\u003e\u003c/w:p\u003e\u003c/w:body\u003e\u003c/w:document\u003e\",\"relationship\":null}],\"relationships\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/document\",\"target\":\"/matlab/document.xml\",\"relationshipId\":\"rId1\"}]}"},{"id":2908,"title":"Approximation of Pi","description":"Pi (divided by 4) can be approximated by the following infinite series:\r\npi/4 = 1 - 1/3 + 1/5 - 1/7 + ...\r\nFor a given number of terms (n), return the difference between the actual value of pi and this approximation of the constant.\r\nAlso, try Problem 2909, a slightly harder variant of this problem.","description_html":"\u003cdiv style = \"text-align: start; line-height: 20.4333px; min-height: 0px; white-space: normal; color: rgb(0, 0, 0); font-family: Menlo, Monaco, Consolas, monospace; font-style: normal; font-size: 14px; font-weight: 400; text-decoration: rgb(0, 0, 0); white-space: normal; \"\u003e\u003cdiv style=\"block-size: 132px; display: block; min-width: 0px; padding-block-start: 0px; padding-top: 0px; perspective-origin: 407px 66px; transform-origin: 407px 66px; vertical-align: baseline; \"\u003e\u003cdiv style=\"block-size: 21px; font-family: Helvetica, Arial, sans-serif; line-height: 21px; margin-block-end: 9px; margin-block-start: 2px; margin-bottom: 9px; margin-inline-end: 10px; margin-inline-start: 4px; margin-left: 4px; margin-right: 10px; margin-top: 2px; perspective-origin: 384px 10.5px; text-align: left; transform-origin: 384px 10.5px; white-space: pre-wrap; margin-left: 4px; margin-top: 2px; margin-bottom: 9px; margin-right: 10px; \"\u003e\u003cspan style=\"block-size: auto; display: inline; margin-block-end: 0px; margin-block-start: 0px; margin-bottom: 0px; margin-inline-end: 0px; margin-inline-start: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; perspective-origin: 215px 8px; transform-origin: 215px 8px; unicode-bidi: normal; \"\u003e\u003cspan style=\"\"\u003ePi (divided by 4) can be approximated by the following infinite series:\u003c/span\u003e\u003c/span\u003e\u003c/div\u003e\u003cdiv style=\"block-size: 21px; font-family: Helvetica, Arial, sans-serif; line-height: 21px; margin-block-end: 9px; margin-block-start: 2px; margin-bottom: 9px; margin-inline-end: 10px; margin-inline-start: 4px; margin-left: 4px; margin-right: 10px; margin-top: 2px; perspective-origin: 384px 10.5px; text-align: left; transform-origin: 384px 10.5px; white-space: pre-wrap; margin-left: 4px; margin-top: 2px; margin-bottom: 9px; margin-right: 10px; \"\u003e\u003cspan style=\"block-size: auto; display: inline; margin-block-end: 0px; margin-block-start: 0px; margin-bottom: 0px; margin-inline-end: 0px; margin-inline-start: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; perspective-origin: 88.5px 8px; transform-origin: 88.5px 8px; unicode-bidi: normal; \"\u003e\u003cspan style=\"\"\u003epi/4 = 1 - 1/3 + 1/5 - 1/7 + ...\u003c/span\u003e\u003c/span\u003e\u003c/div\u003e\u003cdiv style=\"block-size: 42px; font-family: Helvetica, Arial, sans-serif; line-height: 21px; margin-block-end: 9px; margin-block-start: 2px; margin-bottom: 9px; margin-inline-end: 10px; margin-inline-start: 4px; margin-left: 4px; margin-right: 10px; margin-top: 2px; perspective-origin: 384px 21px; text-align: left; transform-origin: 384px 21px; white-space: pre-wrap; margin-left: 4px; margin-top: 2px; margin-bottom: 9px; margin-right: 10px; \"\u003e\u003cspan style=\"block-size: auto; display: inline; margin-block-end: 0px; margin-block-start: 0px; margin-bottom: 0px; margin-inline-end: 0px; margin-inline-start: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; perspective-origin: 360px 8px; transform-origin: 360px 8px; unicode-bidi: normal; \"\u003e\u003cspan style=\"\"\u003eFor a given number of terms (n), return the difference between the actual value of pi and this approximation of the constant.\u003c/span\u003e\u003c/span\u003e\u003c/div\u003e\u003cdiv style=\"block-size: 21px; font-family: Helvetica, Arial, sans-serif; line-height: 21px; margin-block-end: 9px; margin-block-start: 2px; margin-bottom: 9px; margin-inline-end: 10px; margin-inline-start: 4px; margin-left: 4px; margin-right: 10px; margin-top: 2px; perspective-origin: 384px 10.5px; text-align: left; transform-origin: 384px 10.5px; white-space: pre-wrap; margin-left: 4px; margin-top: 2px; margin-bottom: 9px; margin-right: 10px; \"\u003e\u003cspan style=\"block-size: auto; display: inline; margin-block-end: 0px; margin-block-start: 0px; margin-bottom: 0px; margin-inline-end: 0px; margin-inline-start: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; perspective-origin: 25.5px 8px; transform-origin: 25.5px 8px; unicode-bidi: normal; \"\u003e\u003cspan style=\"\"\u003eAlso, try\u003c/span\u003e\u003c/span\u003e\u003cspan style=\"block-size: auto; display: inline; margin-block-end: 0px; margin-block-start: 0px; margin-bottom: 0px; margin-inline-end: 0px; margin-inline-start: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; perspective-origin: 2px 8px; transform-origin: 2px 8px; unicode-bidi: normal; \"\u003e\u003cspan style=\"\"\u003e \u003c/span\u003e\u003c/span\u003e\u003ca target='_blank' href = \"https://www.mathworks.com/matlabcentral/cody/problems/2909-approximation-of-pi-vector-inputs\"\u003e\u003cspan style=\"\"\u003e\u003cspan style=\"\"\u003eProblem 2909\u003c/span\u003e\u003c/span\u003e\u003c/a\u003e\u003cspan style=\"block-size: auto; display: inline; margin-block-end: 0px; margin-block-start: 0px; margin-bottom: 0px; margin-inline-end: 0px; margin-inline-start: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; perspective-origin: 128.5px 8px; transform-origin: 128.5px 8px; unicode-bidi: normal; \"\u003e\u003cspan style=\"\"\u003e, a slightly harder variant of this problem.\u003c/span\u003e\u003c/span\u003e\u003c/div\u003e\u003c/div\u003e\u003c/div\u003e","function_template":"function y = pi_approx(n)\r\n y = n;\r\nend","test_suite":"%%\r\nn = 1;\r\ny_correct = -0.858407346410207;\r\nassert(abs(pi_approx(n)-y_correct)\u003c(100*eps))\r\n\r\n%%\r\nn = 2;\r\ny_correct = 0.474925986923126;\r\nassert(abs(pi_approx(n)-y_correct)\u003c(100*eps)) \r\n\r\n%%\r\nn = 4;\r\ny_correct = 0.246354558351698;\r\nassert(abs(pi_approx(n)-y_correct)\u003c(100*eps))\r\n\r\n%%\r\nn = 7;\r\ny_correct = -0.142145830148691;\r\nassert(abs(pi_approx(n)-y_correct)\u003c(100*eps))\r\n\r\n%%\r\nn = 10;\r\ny_correct = 0.099753034660390;\r\nassert(abs(pi_approx(n)-y_correct)\u003c(100*eps))\r\n\r\n%%\r\nn = 14;\r\ny_correct = 0.071338035810608;\r\nassert(abs(pi_approx(n)-y_correct)\u003c(100*eps))\r\n\r\n%%\r\nn = 17;\r\ny_correct = -0.058772861819756;\r\nassert(abs(pi_approx(n)-y_correct)\u003c(100*eps))\r\n\r\n%%\r\nn = 20;\r\ny_correct = 0.049968846921953;\r\nassert(abs(pi_approx(n)-y_correct)\u003c(100*eps))\r\n\r\n%%\r\nn = 25;\r\ny_correct = -0.039984031845239;\r\nassert(abs(pi_approx(n)-y_correct)\u003c(100*eps))\r\n\r\n%%\r\nn = 42;\r\ny_correct = 0.023806151830915;\r\nassert(abs(pi_approx(n)-y_correct)\u003c(100*eps))\r\n","published":true,"deleted":false,"likes_count":18,"comments_count":0,"created_by":26769,"edited_by":223089,"edited_at":"2022-09-05T17:21:56.000Z","deleted_by":null,"deleted_at":null,"solvers_count":1412,"test_suite_updated_at":"2022-09-05T17:21:56.000Z","rescore_all_solutions":false,"group_id":29,"created_at":"2015-02-01T03:29:10.000Z","updated_at":"2026-04-17T02:25:03.000Z","published_at":"2015-02-01T03:29:10.000Z","restored_at":null,"restored_by":null,"spam":false,"simulink":false,"admin_reviewed":false,"description_opc":"{\"parts\":[{\"partUri\":\"/matlab/document.xml\",\"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\u003cw:jc w:val=\\\"left\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003ePi (divided by 4) can be approximated by the following infinite series:\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\u003epi/4 = 1 - 1/3 + 1/5 - 1/7 + ...\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\u003eFor a given number of terms (n), return the difference between the actual value of pi and this approximation of the constant.\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\u003eAlso, try\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://www.mathworks.com/matlabcentral/cody/problems/2909-approximation-of-pi-vector-inputs\\\"\u003e\u003cw:r\u003e\u003cw:t\u003eProblem 2909\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:hyperlink\u003e\u003cw:r\u003e\u003cw:t\u003e, a slightly harder variant of this problem.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003c/w:body\u003e\u003c/w:document\u003e\",\"relationship\":null}],\"relationships\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/document\",\"target\":\"/matlab/document.xml\",\"relationshipId\":\"rId1\"}]}"},{"id":953,"title":"Pi Estimate 1","description":"Estimate Pi as described in the following link:\r\n\u003chttp://www.people.virginia.edu/~teh1m/cody/Pi_estimation1.pdf\u003e\r\n","description_html":"\u003cdiv style = \"text-align: start; line-height: 20.4333px; min-height: 0px; white-space: normal; color: rgb(0, 0, 0); font-family: Menlo, Monaco, Consolas, monospace; font-style: normal; font-size: 14px; font-weight: 400; text-decoration: rgb(0, 0, 0); white-space: normal; \"\u003e\u003cdiv style=\"block-size: 81px; display: block; min-width: 0px; padding-block-start: 0px; padding-top: 0px; perspective-origin: 407px 40.5px; transform-origin: 407px 40.5px; vertical-align: baseline; \"\u003e\u003cdiv style=\"block-size: 21px; font-family: Helvetica, Arial, sans-serif; line-height: 21px; margin-block-end: 9px; margin-block-start: 2px; margin-bottom: 9px; margin-inline-end: 10px; margin-inline-start: 4px; margin-left: 4px; margin-right: 10px; margin-top: 2px; perspective-origin: 384px 10.5px; text-align: left; transform-origin: 384px 10.5px; white-space: pre-wrap; margin-left: 4px; margin-top: 2px; margin-bottom: 9px; margin-right: 10px; \"\u003e\u003cspan style=\"block-size: auto; display: inline; margin-block-end: 0px; margin-block-start: 0px; margin-bottom: 0px; margin-inline-end: 0px; margin-inline-start: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; perspective-origin: 222.5px 8px; transform-origin: 222.5px 8px; unicode-bidi: normal; \"\u003e\u003cspan style=\"\"\u003eEstimate Pi as described by the Leibniz formula (see the following link):\u003c/span\u003e\u003c/span\u003e\u003c/div\u003e\u003cdiv style=\"block-size: 21px; font-family: Helvetica, Arial, sans-serif; line-height: 21px; margin-block-end: 9px; margin-block-start: 2px; margin-bottom: 9px; margin-inline-end: 10px; margin-inline-start: 4px; margin-left: 4px; margin-right: 10px; margin-top: 2px; perspective-origin: 384px 10.5px; text-align: left; transform-origin: 384px 10.5px; white-space: pre-wrap; margin-left: 4px; margin-top: 2px; margin-bottom: 9px; margin-right: 10px; \"\u003e\u003ca target='_blank' href = \"https://en.wikipedia.org/wiki/Leibniz_formula_for_%CF%80\"\u003e\u003cspan style=\"\"\u003e\u003cspan style=\"\"\u003ehttps://en.wikipedia.org/wiki/Leibniz_formula_for_%CF%80\u003c/span\u003e\u003c/span\u003e\u003c/a\u003e\u003c/div\u003e\u003cdiv style=\"block-size: 21px; font-family: Helvetica, Arial, sans-serif; line-height: 21px; margin-block-end: 9px; margin-block-start: 2px; margin-bottom: 9px; margin-inline-end: 10px; margin-inline-start: 4px; margin-left: 4px; margin-right: 10px; margin-top: 2px; perspective-origin: 384px 10.5px; text-align: left; transform-origin: 384px 10.5px; white-space: pre-wrap; margin-left: 4px; margin-top: 2px; margin-bottom: 9px; margin-right: 10px; \"\u003e\u003cspan style=\"block-size: auto; display: inline; margin-block-end: 0px; margin-block-start: 0px; margin-bottom: 0px; margin-inline-end: 0px; margin-inline-start: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; perspective-origin: 121px 8px; transform-origin: 121px 8px; unicode-bidi: normal; \"\u003e\u003cspan style=\"\"\u003eRound the result to six decimal places.\u003c/span\u003e\u003c/span\u003e\u003c/div\u003e\u003c/div\u003e\u003c/div\u003e","function_template":"function [estimate] = pi_est1(nMax)\r\nestimate = nMax;\r\nend","test_suite":"%%\r\nnMax = 10;\r\ny_correct = 3.041840000000000;\r\nassert(isequal(pi_est1(nMax),y_correct))\r\n%%\r\nnMax = 1000;\r\ny_correct = 3.140593000000000;\r\nassert(isequal(pi_est1(nMax),y_correct))\r\n%%\r\nnMax = 1e6;\r\ny_correct = 3.141592000000000;\r\nassert(isequal(pi_est1(nMax),y_correct))\r\n","published":true,"deleted":false,"likes_count":20,"comments_count":19,"created_by":2640,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":1803,"test_suite_updated_at":"2020-10-03T14:08:03.000Z","rescore_all_solutions":false,"group_id":1,"created_at":"2012-09-20T21:16:13.000Z","updated_at":"2026-04-17T02:09:21.000Z","published_at":"2012-09-20T23:13:59.000Z","restored_at":null,"restored_by":null,"spam":false,"simulink":false,"admin_reviewed":false,"description_opc":"{\"parts\":[{\"partUri\":\"/matlab/document.xml\",\"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\u003cw:jc w:val=\\\"left\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eEstimate Pi as described by the Leibniz formula (see the following link):\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:hyperlink w:docLocation=\\\"https://en.wikipedia.org/wiki/Leibniz_formula_for_%CF%80\\\"\u003e\u003cw:r\u003e\u003cw:t\u003ehttps://en.wikipedia.org/wiki/Leibniz_formula_for_%CF%80\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:hyperlink\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\u003eRound the result to six decimal places.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003c/w:body\u003e\u003c/w:document\u003e\",\"relationship\":null}],\"relationships\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/document\",\"target\":\"/matlab/document.xml\",\"relationshipId\":\"rId1\"}]}"},{"id":44309,"title":"Pi Digit Probability","description":"Assume that the next digit of pi constant is determined by the historical digit distribution. What is the probability of next digit (N) being (n). \r\n\r\nFor example if we consider the first 100 digits of pi, we will see that the digit '3' is occured 12 times. So the probability of the being '3' the 101th digit will be 12/100 = 0.12.\r\n\r\nRound the results to four decimals.","description_html":"\u003cp\u003eAssume that the next digit of pi constant is determined by the historical digit distribution. What is the probability of next digit (N) being (n).\u003c/p\u003e\u003cp\u003eFor example if we consider the first 100 digits of pi, we will see that the digit '3' is occured 12 times. So the probability of the being '3' the 101th digit will be 12/100 = 0.12.\u003c/p\u003e\u003cp\u003eRound the results to four decimals.\u003c/p\u003e","function_template":"function y = pidigit(N,n)\r\n  y = x;\r\nend","test_suite":"%%\r\nN = 101;\r\nn = 3;\r\ny_correct = 0.1200;\r\nassert(abs(pidigit(N,n)-y_correct)\u003c0.0001)\r\nassert(~any(cellfun(@(x)ismember(max([0,str2num(x)]),[101,201,202,203,1001]),regexp(fileread('pidigit.m'),'[\\d\\.\\+\\-\\*\\/]+','match')))) % modified from the comment of Alfonso on https://www.mathworks.com/matlabcentral/cody/problems/44343\r\n\r\n%%\r\nN = 201;\r\nn = 6;\r\ny_correct = 0.0750;\r\nassert(abs(pidigit(N,n)-y_correct)\u003c0.0001)\r\nassert(~any(cellfun(@(x)ismember(max([0,str2num(x)]),[101,201,202,203,1001]),regexp(fileread('pidigit.m'),'[\\d\\.\\+\\-\\*\\/]+','match'))))\r\n\r\n%%\r\nN = 202;\r\nn = 6;\r\ny_correct = 0.0796;\r\nassert(abs(pidigit(N,n)-y_correct)\u003c0.0001)\r\nassert(~any(cellfun(@(x)ismember(max([0,str2num(x)]),[101,201,202,203,1001]),regexp(fileread('pidigit.m'),'[\\d\\.\\+\\-\\*\\/]+','match'))))\r\n\r\n%%\r\nN = 203;\r\nn = 6;\r\ny_correct = 0.0792;\r\nassert(abs(pidigit(N,n)-y_correct)\u003c0.0001)\r\nassert(~any(cellfun(@(x)ismember(max([0,str2num(x)]),[101,201,202,203,1001]),regexp(fileread('pidigit.m'),'[\\d\\.\\+\\-\\*\\/]+','match'))))\r\n\r\n%%\r\nN = 1001;\r\nn = 9;\r\ny_correct = 0.1050;\r\nassert(abs(pidigit(N,n)-y_correct)\u003c0.0001)\r\nassert(~any(cellfun(@(x)ismember(max([0,str2num(x)]),[101,201,202,203,1001]),regexp(fileread('pidigit.m'),'[\\d\\.\\+\\-\\*\\/]+','match'))))\r\n","published":true,"deleted":false,"likes_count":18,"comments_count":27,"created_by":8703,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":853,"test_suite_updated_at":"2017-10-21T07:59:48.000Z","rescore_all_solutions":false,"group_id":34,"created_at":"2017-09-11T06:41:07.000Z","updated_at":"2026-04-17T02:20:31.000Z","published_at":"2017-10-16T01:45:06.000Z","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\u003eAssume that the next digit of pi constant is determined by the historical digit distribution. What is the probability of next digit (N) being (n).\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\u003eFor example if we consider the first 100 digits of pi, we will see that the digit '3' is occured 12 times. So the probability of the being '3' the 101th digit will be 12/100 = 0.12.\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\u003eRound the results to four decimals.\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":43298,"title":"Calculate area of sector","description":"A=function(r,seta)\r\n\r\nr is radius of sector, seta is angle of sector, and A is its area. Area of sector A is defined as 0.5*(r^2)*seta;","description_html":"\u003cdiv style = \"text-align: start; line-height: 20.44px; min-height: 0px; white-space: normal; color: rgb(0, 0, 0); font-family: Menlo, Monaco, Consolas, monospace; font-style: normal; font-size: 14px; font-weight: 400; text-decoration: none solid rgb(0, 0, 0); white-space: normal; \"\u003e\u003cdiv style=\"block-size: 51px; display: block; min-width: 0px; padding-block-start: 0px; padding-top: 0px; perspective-origin: 407px 25.5px; transform-origin: 407px 25.5px; vertical-align: baseline; \"\u003e\u003cdiv style=\"block-size: 21px; font-family: Helvetica, Arial, sans-serif; line-height: 21px; margin-block-end: 9px; margin-block-start: 2px; margin-bottom: 9px; margin-inline-end: 10px; margin-inline-start: 4px; margin-left: 4px; margin-right: 10px; margin-top: 2px; perspective-origin: 384px 10.5px; text-align: left; transform-origin: 384px 10.5px; white-space: pre-wrap; margin-left: 4px; margin-top: 2px; margin-bottom: 9px; margin-right: 10px; \"\u003e\u003cspan style=\"block-size: auto; display: inline; margin-block-end: 0px; margin-block-start: 0px; margin-bottom: 0px; margin-inline-end: 0px; margin-inline-start: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; perspective-origin: 0px 0px; transform-origin: 0px 0px; \"\u003e\u003cspan style=\"\"\u003eA=function(r,seta)\u003c/span\u003e\u003c/span\u003e\u003c/div\u003e\u003cdiv style=\"block-size: 21px; font-family: Helvetica, Arial, sans-serif; line-height: 21px; margin-block-end: 9px; margin-block-start: 2px; margin-bottom: 9px; margin-inline-end: 10px; margin-inline-start: 4px; margin-left: 4px; margin-right: 10px; margin-top: 2px; perspective-origin: 384px 10.5px; text-align: left; transform-origin: 384px 10.5px; white-space: pre-wrap; margin-left: 4px; margin-top: 2px; margin-bottom: 9px; margin-right: 10px; \"\u003e\u003cspan style=\"block-size: auto; display: inline; margin-block-end: 0px; margin-block-start: 0px; margin-bottom: 0px; margin-inline-end: 0px; margin-inline-start: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; perspective-origin: 0px 0px; transform-origin: 0px 0px; \"\u003e\u003cspan style=\"\"\u003er(m) is radius of sector, seta (radian) is angle of sector, and A (m^2) is its area.\u003c/span\u003e\u003c/span\u003e\u003c/div\u003e\u003c/div\u003e\u003c/div\u003e","function_template":"function y = sectorarea(r,seta)\r\n  y =\r\nend","test_suite":"%%\r\nr=1\r\nseta=pi/2\r\ny_correct = 0.7854;\r\nassert(abs(sectorarea(r,seta)-y_correct)\u003c0.001)\r\n\r\n%%\r\nr=2\r\nseta=pi/2\r\ny_correct = pi;\r\nassert(abs(sectorarea(r,seta)-y_correct)\u003c0.001)\r\n\r\n%%\r\nr=sqrt(2);\r\nseta=pi/3\r\ny_correct = pi/3;\r\nassert(abs(sectorarea(r,seta)-y_correct)\u003c0.001)\r\n\r\n%%\r\nr= 6\r\nseta=pi/6;\r\ny_correct = 3*pi;\r\nassert(abs(sectorarea(r,seta)-y_correct)\u003c0.001)\r\n\r\n%%\r\nr= pi\r\nseta= pi\r\ny_correct = 0.5*pi^3;\r\nassert(abs(sectorarea(r,seta)-y_correct)\u003c0.001)\r\n","published":true,"deleted":false,"likes_count":21,"comments_count":6,"created_by":33533,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":3480,"test_suite_updated_at":"2021-02-21T07:46:40.000Z","rescore_all_solutions":true,"group_id":1,"created_at":"2016-10-10T09:02:12.000Z","updated_at":"2026-04-17T02:07:35.000Z","published_at":"2016-10-10T09:02:12.000Z","restored_at":null,"restored_by":null,"spam":false,"simulink":false,"admin_reviewed":false,"description_opc":"{\"parts\":[{\"partUri\":\"/matlab/document.xml\",\"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\u003cw:jc w:val=\\\"left\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eA=function(r,seta)\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\u003er(m) is radius of sector, seta (radian) is angle of sector, and A (m^2) is its area.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003c/w:body\u003e\u003c/w:document\u003e\",\"relationship\":null}],\"relationships\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/document\",\"target\":\"/matlab/document.xml\",\"relationshipId\":\"rId1\"}]}"},{"id":44273,"title":"Given a square and a circle, please decide whether the square covers more area.","description":"You know the side of a square and the diameter of a circle, please decide whether the square covers more area.","description_html":"\u003cp\u003eYou know the side of a square and the diameter of a circle, please decide whether the square covers more area.\u003c/p\u003e","function_template":"function y = sqci(sq,ci)\r\n  y = (sq\u003eci);\r\nend","test_suite":"%%\r\nsq = 2;\r\nci = 1;\r\ny_correct = (sq\u003eci);\r\nassert(isequal(sqci(sq,ci),y_correct))\r\n\r\n%%\r\nsq = rand;\r\nci = rand;\r\ny_correct = (4*sq^2\u003epi*ci^2);\r\nassert(isequal(sqci(sq,ci),y_correct))\r\n\r\n%%\r\nsq = 0;\r\nci = 0;\r\ny_correct = (0\u003e0);\r\nassert(isequal(sqci(sq,ci),y_correct))\r\n\r\n%%\r\nsq = 100;\r\nci = 4;\r\ny_correct = (7\u003e3);\r\nassert(isequal(sqci(sq,ci),y_correct))\r\n\r\n%%\r\nsq = 21;\r\nci = 127;\r\ny_correct = (3\u003e7);\r\nassert(isequal(sqci(sq,ci),y_correct))\r\n","published":true,"deleted":false,"likes_count":8,"comments_count":3,"created_by":166,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":1747,"test_suite_updated_at":"2017-08-06T18:26:25.000Z","rescore_all_solutions":false,"group_id":1,"created_at":"2017-08-02T14:15:00.000Z","updated_at":"2026-04-17T02:28:23.000Z","published_at":"2017-08-02T14:15:06.000Z","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\u003eYou know the side of a square and the diameter of a circle, please decide whether the square covers more area.\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":954,"title":"Pi Estimate 2","description":"Estimate Pi as described in the following link: http://www.people.virginia.edu/~teh1m/cody/Pi_estimation2.pdf","description_html":"\u003cdiv style = \"text-align: start; line-height: 20.4333px; min-height: 0px; white-space: normal; color: rgb(0, 0, 0); font-family: Menlo, Monaco, Consolas, monospace; font-style: normal; font-size: 14px; font-weight: 400; text-decoration: rgb(0, 0, 0); white-space: normal; \"\u003e\u003cdiv style=\"block-size: 21px; display: block; min-width: 0px; padding-block-start: 0px; padding-top: 0px; perspective-origin: 407px 10.5px; transform-origin: 407px 10.5px; vertical-align: baseline; \"\u003e\u003cdiv style=\"font-family: Helvetica, Arial, sans-serif; line-height: 21px; margin-block-end: 9px; margin-block-start: 2px; margin-bottom: 9px; margin-inline-end: 10px; margin-inline-start: 4px; margin-left: 4px; margin-right: 10px; margin-top: 2px; perspective-origin: 384px 10.5px; text-align: left; transform-origin: 384px 10.5px; white-space: pre-wrap; margin-left: 4px; margin-top: 2px; margin-bottom: 9px; margin-right: 10px; \"\u003e\u003cspan style=\"block-size: auto; display: inline; margin-block-end: 0px; margin-block-start: 0px; margin-bottom: 0px; margin-inline-end: 0px; margin-inline-start: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; perspective-origin: 140.5px 8px; transform-origin: 140.5px 8px; unicode-bidi: normal; \"\u003e\u003cspan style=\"\"\u003eEstimate Pi as described in the following link:\u003c/span\u003e\u003c/span\u003e\u003cspan style=\"block-size: auto; display: inline; margin-block-end: 0px; margin-block-start: 0px; margin-bottom: 0px; margin-inline-end: 0px; margin-inline-start: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; perspective-origin: 2px 8px; transform-origin: 2px 8px; unicode-bidi: normal; \"\u003e\u003cspan style=\"\"\u003e \u003c/span\u003e\u003c/span\u003e\u003ca target='_blank' href = \"/#null\"\u003e\u003cspan style=\"\"\u003e\u003cspan style=\"\"\u003ehttp://www.people.virginia.edu/~teh1m/cody/Pi_estimation2.pdf\u003c/span\u003e\u003c/span\u003e\u003c/a\u003e\u003c/div\u003e\u003c/div\u003e\u003c/div\u003e","function_template":"function [output] = pi_est2(d)\r\n  n=d;\r\n  estimate=d;\r\n  output = [ n  estimate]\r\nend","test_suite":"%%\r\nfiletext = fileread('pi_est2.m');\r\nillegal = contains(filetext, 'str2num') ||  contains(filetext, 'switch'); \r\nassert(~illegal)\r\n\r\n%%\r\nx = 6;\r\ny_correct = [11  3.141592442800000];\r\nassert(isequal(pi_est2(x),y_correct))\r\n%%\r\nx = 4;\r\ny_correct = [8 3.141577086000000];\r\nassert(isequal(pi_est2(x),y_correct))\r\n%%\r\nx = 8;\r\ny_correct = [14 3.141592650600000];\r\nassert(isequal(pi_est2(x),y_correct))\r\n","published":true,"deleted":false,"likes_count":1,"comments_count":10,"created_by":2640,"edited_by":223089,"edited_at":"2022-10-11T11:17:31.000Z","deleted_by":null,"deleted_at":null,"solvers_count":48,"test_suite_updated_at":"2022-10-11T11:17:31.000Z","rescore_all_solutions":false,"group_id":1,"created_at":"2012-09-22T21:49:49.000Z","updated_at":"2026-01-08T21:53:05.000Z","published_at":"2012-09-23T15:59:23.000Z","restored_at":null,"restored_by":null,"spam":null,"simulink":false,"admin_reviewed":false,"description_opc":"{\"parts\":[{\"partUri\":\"/matlab/document.xml\",\"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\u003cw:jc w:val=\\\"left\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eEstimate Pi as described in the following link:\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=\\\"\\\"\u003e\u003cw:r\u003e\u003cw:t\u003ehttp://www.people.virginia.edu/~teh1m/cody/Pi_estimation2.pdf\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:hyperlink\u003e\u003c/w:p\u003e\u003c/w:body\u003e\u003c/w:document\u003e\",\"relationship\":null}],\"relationships\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/document\",\"target\":\"/matlab/document.xml\",\"relationshipId\":\"rId1\"}]}"},{"id":2908,"title":"Approximation of Pi","description":"Pi (divided by 4) can be approximated by the following infinite series:\r\npi/4 = 1 - 1/3 + 1/5 - 1/7 + ...\r\nFor a given number of terms (n), return the difference between the actual value of pi and this approximation of the constant.\r\nAlso, try Problem 2909, a slightly harder variant of this problem.","description_html":"\u003cdiv style = \"text-align: start; line-height: 20.4333px; min-height: 0px; white-space: normal; color: rgb(0, 0, 0); font-family: Menlo, Monaco, Consolas, monospace; font-style: normal; font-size: 14px; font-weight: 400; text-decoration: rgb(0, 0, 0); white-space: normal; \"\u003e\u003cdiv style=\"block-size: 132px; display: block; min-width: 0px; padding-block-start: 0px; padding-top: 0px; perspective-origin: 407px 66px; transform-origin: 407px 66px; vertical-align: baseline; \"\u003e\u003cdiv style=\"block-size: 21px; font-family: Helvetica, Arial, sans-serif; line-height: 21px; margin-block-end: 9px; margin-block-start: 2px; margin-bottom: 9px; margin-inline-end: 10px; margin-inline-start: 4px; margin-left: 4px; margin-right: 10px; margin-top: 2px; perspective-origin: 384px 10.5px; text-align: left; transform-origin: 384px 10.5px; white-space: pre-wrap; margin-left: 4px; margin-top: 2px; margin-bottom: 9px; margin-right: 10px; \"\u003e\u003cspan style=\"block-size: auto; display: inline; margin-block-end: 0px; margin-block-start: 0px; margin-bottom: 0px; margin-inline-end: 0px; margin-inline-start: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; perspective-origin: 215px 8px; transform-origin: 215px 8px; unicode-bidi: normal; \"\u003e\u003cspan style=\"\"\u003ePi (divided by 4) can be approximated by the following infinite series:\u003c/span\u003e\u003c/span\u003e\u003c/div\u003e\u003cdiv style=\"block-size: 21px; font-family: Helvetica, Arial, sans-serif; line-height: 21px; margin-block-end: 9px; margin-block-start: 2px; margin-bottom: 9px; margin-inline-end: 10px; margin-inline-start: 4px; margin-left: 4px; margin-right: 10px; margin-top: 2px; perspective-origin: 384px 10.5px; text-align: left; transform-origin: 384px 10.5px; white-space: pre-wrap; margin-left: 4px; margin-top: 2px; margin-bottom: 9px; margin-right: 10px; \"\u003e\u003cspan style=\"block-size: auto; display: inline; margin-block-end: 0px; margin-block-start: 0px; margin-bottom: 0px; margin-inline-end: 0px; margin-inline-start: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; perspective-origin: 88.5px 8px; transform-origin: 88.5px 8px; unicode-bidi: normal; \"\u003e\u003cspan style=\"\"\u003epi/4 = 1 - 1/3 + 1/5 - 1/7 + ...\u003c/span\u003e\u003c/span\u003e\u003c/div\u003e\u003cdiv style=\"block-size: 42px; font-family: Helvetica, Arial, sans-serif; line-height: 21px; margin-block-end: 9px; margin-block-start: 2px; margin-bottom: 9px; margin-inline-end: 10px; margin-inline-start: 4px; margin-left: 4px; margin-right: 10px; margin-top: 2px; perspective-origin: 384px 21px; text-align: left; transform-origin: 384px 21px; white-space: pre-wrap; margin-left: 4px; margin-top: 2px; margin-bottom: 9px; margin-right: 10px; \"\u003e\u003cspan style=\"block-size: auto; display: inline; margin-block-end: 0px; margin-block-start: 0px; margin-bottom: 0px; margin-inline-end: 0px; margin-inline-start: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; perspective-origin: 360px 8px; transform-origin: 360px 8px; unicode-bidi: normal; \"\u003e\u003cspan style=\"\"\u003eFor a given number of terms (n), return the difference between the actual value of pi and this approximation of the constant.\u003c/span\u003e\u003c/span\u003e\u003c/div\u003e\u003cdiv style=\"block-size: 21px; font-family: Helvetica, Arial, sans-serif; line-height: 21px; margin-block-end: 9px; margin-block-start: 2px; margin-bottom: 9px; margin-inline-end: 10px; margin-inline-start: 4px; margin-left: 4px; margin-right: 10px; margin-top: 2px; perspective-origin: 384px 10.5px; text-align: left; transform-origin: 384px 10.5px; white-space: pre-wrap; margin-left: 4px; margin-top: 2px; margin-bottom: 9px; margin-right: 10px; \"\u003e\u003cspan style=\"block-size: auto; display: inline; margin-block-end: 0px; margin-block-start: 0px; margin-bottom: 0px; margin-inline-end: 0px; margin-inline-start: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; perspective-origin: 25.5px 8px; transform-origin: 25.5px 8px; unicode-bidi: normal; \"\u003e\u003cspan style=\"\"\u003eAlso, try\u003c/span\u003e\u003c/span\u003e\u003cspan style=\"block-size: auto; display: inline; margin-block-end: 0px; margin-block-start: 0px; margin-bottom: 0px; margin-inline-end: 0px; margin-inline-start: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; perspective-origin: 2px 8px; transform-origin: 2px 8px; unicode-bidi: normal; \"\u003e\u003cspan style=\"\"\u003e \u003c/span\u003e\u003c/span\u003e\u003ca target='_blank' href = \"https://www.mathworks.com/matlabcentral/cody/problems/2909-approximation-of-pi-vector-inputs\"\u003e\u003cspan style=\"\"\u003e\u003cspan style=\"\"\u003eProblem 2909\u003c/span\u003e\u003c/span\u003e\u003c/a\u003e\u003cspan style=\"block-size: auto; display: inline; margin-block-end: 0px; margin-block-start: 0px; margin-bottom: 0px; margin-inline-end: 0px; margin-inline-start: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; perspective-origin: 128.5px 8px; transform-origin: 128.5px 8px; unicode-bidi: normal; \"\u003e\u003cspan style=\"\"\u003e, a slightly harder variant of this problem.\u003c/span\u003e\u003c/span\u003e\u003c/div\u003e\u003c/div\u003e\u003c/div\u003e","function_template":"function y = pi_approx(n)\r\n y = n;\r\nend","test_suite":"%%\r\nn = 1;\r\ny_correct = -0.858407346410207;\r\nassert(abs(pi_approx(n)-y_correct)\u003c(100*eps))\r\n\r\n%%\r\nn = 2;\r\ny_correct = 0.474925986923126;\r\nassert(abs(pi_approx(n)-y_correct)\u003c(100*eps)) \r\n\r\n%%\r\nn = 4;\r\ny_correct = 0.246354558351698;\r\nassert(abs(pi_approx(n)-y_correct)\u003c(100*eps))\r\n\r\n%%\r\nn = 7;\r\ny_correct = -0.142145830148691;\r\nassert(abs(pi_approx(n)-y_correct)\u003c(100*eps))\r\n\r\n%%\r\nn = 10;\r\ny_correct = 0.099753034660390;\r\nassert(abs(pi_approx(n)-y_correct)\u003c(100*eps))\r\n\r\n%%\r\nn = 14;\r\ny_correct = 0.071338035810608;\r\nassert(abs(pi_approx(n)-y_correct)\u003c(100*eps))\r\n\r\n%%\r\nn = 17;\r\ny_correct = -0.058772861819756;\r\nassert(abs(pi_approx(n)-y_correct)\u003c(100*eps))\r\n\r\n%%\r\nn = 20;\r\ny_correct = 0.049968846921953;\r\nassert(abs(pi_approx(n)-y_correct)\u003c(100*eps))\r\n\r\n%%\r\nn = 25;\r\ny_correct = -0.039984031845239;\r\nassert(abs(pi_approx(n)-y_correct)\u003c(100*eps))\r\n\r\n%%\r\nn = 42;\r\ny_correct = 0.023806151830915;\r\nassert(abs(pi_approx(n)-y_correct)\u003c(100*eps))\r\n","published":true,"deleted":false,"likes_count":18,"comments_count":0,"created_by":26769,"edited_by":223089,"edited_at":"2022-09-05T17:21:56.000Z","deleted_by":null,"deleted_at":null,"solvers_count":1412,"test_suite_updated_at":"2022-09-05T17:21:56.000Z","rescore_all_solutions":false,"group_id":29,"created_at":"2015-02-01T03:29:10.000Z","updated_at":"2026-04-17T02:25:03.000Z","published_at":"2015-02-01T03:29:10.000Z","restored_at":null,"restored_by":null,"spam":false,"simulink":false,"admin_reviewed":false,"description_opc":"{\"parts\":[{\"partUri\":\"/matlab/document.xml\",\"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\u003cw:jc w:val=\\\"left\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003ePi (divided by 4) can be approximated by the following infinite series:\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\u003epi/4 = 1 - 1/3 + 1/5 - 1/7 + ...\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\u003eFor a given number of terms (n), return the difference between the actual value of pi and this approximation of the constant.\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\u003eAlso, try\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://www.mathworks.com/matlabcentral/cody/problems/2909-approximation-of-pi-vector-inputs\\\"\u003e\u003cw:r\u003e\u003cw:t\u003eProblem 2909\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:hyperlink\u003e\u003cw:r\u003e\u003cw:t\u003e, a slightly harder variant of this problem.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003c/w:body\u003e\u003c/w:document\u003e\",\"relationship\":null}],\"relationships\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/document\",\"target\":\"/matlab/document.xml\",\"relationshipId\":\"rId1\"}]}"},{"id":953,"title":"Pi Estimate 1","description":"Estimate Pi as described in the following link:\r\n\u003chttp://www.people.virginia.edu/~teh1m/cody/Pi_estimation1.pdf\u003e\r\n","description_html":"\u003cdiv style = \"text-align: start; line-height: 20.4333px; min-height: 0px; white-space: normal; color: rgb(0, 0, 0); font-family: Menlo, Monaco, Consolas, monospace; font-style: normal; font-size: 14px; font-weight: 400; text-decoration: rgb(0, 0, 0); white-space: normal; \"\u003e\u003cdiv style=\"block-size: 81px; display: block; min-width: 0px; padding-block-start: 0px; padding-top: 0px; perspective-origin: 407px 40.5px; transform-origin: 407px 40.5px; vertical-align: baseline; \"\u003e\u003cdiv style=\"block-size: 21px; font-family: Helvetica, Arial, sans-serif; line-height: 21px; margin-block-end: 9px; margin-block-start: 2px; margin-bottom: 9px; margin-inline-end: 10px; margin-inline-start: 4px; margin-left: 4px; margin-right: 10px; margin-top: 2px; perspective-origin: 384px 10.5px; text-align: left; transform-origin: 384px 10.5px; white-space: pre-wrap; margin-left: 4px; margin-top: 2px; margin-bottom: 9px; margin-right: 10px; \"\u003e\u003cspan style=\"block-size: auto; display: inline; margin-block-end: 0px; margin-block-start: 0px; margin-bottom: 0px; margin-inline-end: 0px; margin-inline-start: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; perspective-origin: 222.5px 8px; transform-origin: 222.5px 8px; unicode-bidi: normal; \"\u003e\u003cspan style=\"\"\u003eEstimate Pi as described by the Leibniz formula (see the following link):\u003c/span\u003e\u003c/span\u003e\u003c/div\u003e\u003cdiv style=\"block-size: 21px; font-family: Helvetica, Arial, sans-serif; line-height: 21px; margin-block-end: 9px; margin-block-start: 2px; margin-bottom: 9px; margin-inline-end: 10px; margin-inline-start: 4px; margin-left: 4px; margin-right: 10px; margin-top: 2px; perspective-origin: 384px 10.5px; text-align: left; transform-origin: 384px 10.5px; white-space: pre-wrap; margin-left: 4px; margin-top: 2px; margin-bottom: 9px; margin-right: 10px; \"\u003e\u003ca target='_blank' href = \"https://en.wikipedia.org/wiki/Leibniz_formula_for_%CF%80\"\u003e\u003cspan style=\"\"\u003e\u003cspan style=\"\"\u003ehttps://en.wikipedia.org/wiki/Leibniz_formula_for_%CF%80\u003c/span\u003e\u003c/span\u003e\u003c/a\u003e\u003c/div\u003e\u003cdiv style=\"block-size: 21px; font-family: Helvetica, Arial, sans-serif; line-height: 21px; margin-block-end: 9px; margin-block-start: 2px; margin-bottom: 9px; margin-inline-end: 10px; margin-inline-start: 4px; margin-left: 4px; margin-right: 10px; margin-top: 2px; perspective-origin: 384px 10.5px; text-align: left; transform-origin: 384px 10.5px; white-space: pre-wrap; margin-left: 4px; margin-top: 2px; margin-bottom: 9px; margin-right: 10px; \"\u003e\u003cspan style=\"block-size: auto; display: inline; margin-block-end: 0px; margin-block-start: 0px; margin-bottom: 0px; margin-inline-end: 0px; margin-inline-start: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; perspective-origin: 121px 8px; transform-origin: 121px 8px; unicode-bidi: normal; \"\u003e\u003cspan style=\"\"\u003eRound the result to six decimal places.\u003c/span\u003e\u003c/span\u003e\u003c/div\u003e\u003c/div\u003e\u003c/div\u003e","function_template":"function [estimate] = pi_est1(nMax)\r\nestimate = nMax;\r\nend","test_suite":"%%\r\nnMax = 10;\r\ny_correct = 3.041840000000000;\r\nassert(isequal(pi_est1(nMax),y_correct))\r\n%%\r\nnMax = 1000;\r\ny_correct = 3.140593000000000;\r\nassert(isequal(pi_est1(nMax),y_correct))\r\n%%\r\nnMax = 1e6;\r\ny_correct = 3.141592000000000;\r\nassert(isequal(pi_est1(nMax),y_correct))\r\n","published":true,"deleted":false,"likes_count":20,"comments_count":19,"created_by":2640,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":1803,"test_suite_updated_at":"2020-10-03T14:08:03.000Z","rescore_all_solutions":false,"group_id":1,"created_at":"2012-09-20T21:16:13.000Z","updated_at":"2026-04-17T02:09:21.000Z","published_at":"2012-09-20T23:13:59.000Z","restored_at":null,"restored_by":null,"spam":false,"simulink":false,"admin_reviewed":false,"description_opc":"{\"parts\":[{\"partUri\":\"/matlab/document.xml\",\"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\u003cw:jc w:val=\\\"left\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eEstimate Pi as described by the Leibniz formula (see the following link):\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:hyperlink w:docLocation=\\\"https://en.wikipedia.org/wiki/Leibniz_formula_for_%CF%80\\\"\u003e\u003cw:r\u003e\u003cw:t\u003ehttps://en.wikipedia.org/wiki/Leibniz_formula_for_%CF%80\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:hyperlink\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\u003eRound the result to six decimal places.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003c/w:body\u003e\u003c/w:document\u003e\",\"relationship\":null}],\"relationships\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/document\",\"target\":\"/matlab/document.xml\",\"relationshipId\":\"rId1\"}]}"},{"id":44309,"title":"Pi Digit Probability","description":"Assume that the next digit of pi constant is determined by the historical digit distribution. What is the probability of next digit (N) being (n). \r\n\r\nFor example if we consider the first 100 digits of pi, we will see that the digit '3' is occured 12 times. So the probability of the being '3' the 101th digit will be 12/100 = 0.12.\r\n\r\nRound the results to four decimals.","description_html":"\u003cp\u003eAssume that the next digit of pi constant is determined by the historical digit distribution. What is the probability of next digit (N) being (n).\u003c/p\u003e\u003cp\u003eFor example if we consider the first 100 digits of pi, we will see that the digit '3' is occured 12 times. So the probability of the being '3' the 101th digit will be 12/100 = 0.12.\u003c/p\u003e\u003cp\u003eRound the results to four decimals.\u003c/p\u003e","function_template":"function y = pidigit(N,n)\r\n  y = x;\r\nend","test_suite":"%%\r\nN = 101;\r\nn = 3;\r\ny_correct = 0.1200;\r\nassert(abs(pidigit(N,n)-y_correct)\u003c0.0001)\r\nassert(~any(cellfun(@(x)ismember(max([0,str2num(x)]),[101,201,202,203,1001]),regexp(fileread('pidigit.m'),'[\\d\\.\\+\\-\\*\\/]+','match')))) % modified from the comment of Alfonso on https://www.mathworks.com/matlabcentral/cody/problems/44343\r\n\r\n%%\r\nN = 201;\r\nn = 6;\r\ny_correct = 0.0750;\r\nassert(abs(pidigit(N,n)-y_correct)\u003c0.0001)\r\nassert(~any(cellfun(@(x)ismember(max([0,str2num(x)]),[101,201,202,203,1001]),regexp(fileread('pidigit.m'),'[\\d\\.\\+\\-\\*\\/]+','match'))))\r\n\r\n%%\r\nN = 202;\r\nn = 6;\r\ny_correct = 0.0796;\r\nassert(abs(pidigit(N,n)-y_correct)\u003c0.0001)\r\nassert(~any(cellfun(@(x)ismember(max([0,str2num(x)]),[101,201,202,203,1001]),regexp(fileread('pidigit.m'),'[\\d\\.\\+\\-\\*\\/]+','match'))))\r\n\r\n%%\r\nN = 203;\r\nn = 6;\r\ny_correct = 0.0792;\r\nassert(abs(pidigit(N,n)-y_correct)\u003c0.0001)\r\nassert(~any(cellfun(@(x)ismember(max([0,str2num(x)]),[101,201,202,203,1001]),regexp(fileread('pidigit.m'),'[\\d\\.\\+\\-\\*\\/]+','match'))))\r\n\r\n%%\r\nN = 1001;\r\nn = 9;\r\ny_correct = 0.1050;\r\nassert(abs(pidigit(N,n)-y_correct)\u003c0.0001)\r\nassert(~any(cellfun(@(x)ismember(max([0,str2num(x)]),[101,201,202,203,1001]),regexp(fileread('pidigit.m'),'[\\d\\.\\+\\-\\*\\/]+','match'))))\r\n","published":true,"deleted":false,"likes_count":18,"comments_count":27,"created_by":8703,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":853,"test_suite_updated_at":"2017-10-21T07:59:48.000Z","rescore_all_solutions":false,"group_id":34,"created_at":"2017-09-11T06:41:07.000Z","updated_at":"2026-04-17T02:20:31.000Z","published_at":"2017-10-16T01:45:06.000Z","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\u003eAssume that the next digit of pi constant is determined by the historical digit distribution. What is the probability of next digit (N) being (n).\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\u003eFor example if we consider the first 100 digits of pi, we will see that the digit '3' is occured 12 times. 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