{"group":{"id":1,"name":"Community","lockable":false,"created_at":"2012-01-18T18:02:15.000Z","updated_at":"2025-12-14T01:33:56.000Z","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":"2025-12-14T00:00:00.000Z","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":3006,"title":"Test Driven Solution - Probability Problem 2","description":"*Problem:* Without any Cody cheats, write code that passes the test suite.\r\n\r\n*Hint:* The test suite gets samples from the probability distribution represented by your code.  A cumulative distribution function is then built from the samples.  This is the empirical distribution, which is compared against the theoretical distribution you must infer from the test suite.\r\n\r\n*See also:* \u003chttp://en.wikipedia.org/wiki/Cumulative_distribution_function Cumulative Distribution Function\u003e\r\n\r\n*Problems in Series:* \u003chttp://www.mathworks.com/matlabcentral/cody/problems/2995-test-driven-solution-probability-problem-1 Probability Problem 1\u003e, \u003chttp://www.mathworks.com/matlabcentral/cody/problems/3009-test-driven-solution-probability-problem-3 Probability Problem 3\u003e","description_html":"\u003cp\u003e\u003cb\u003eProblem:\u003c/b\u003e Without any Cody cheats, write code that passes the test suite.\u003c/p\u003e\u003cp\u003e\u003cb\u003eHint:\u003c/b\u003e The test suite gets samples from the probability distribution represented by your code.  A cumulative distribution function is then built from the samples.  This is the empirical distribution, which is compared against the theoretical distribution you must infer from the test suite.\u003c/p\u003e\u003cp\u003e\u003cb\u003eSee also:\u003c/b\u003e \u003ca href = \"http://en.wikipedia.org/wiki/Cumulative_distribution_function\"\u003eCumulative Distribution Function\u003c/a\u003e\u003c/p\u003e\u003cp\u003e\u003cb\u003eProblems in Series:\u003c/b\u003e \u003ca href = \"http://www.mathworks.com/matlabcentral/cody/problems/2995-test-driven-solution-probability-problem-1\"\u003eProbability Problem 1\u003c/a\u003e, \u003ca href = \"http://www.mathworks.com/matlabcentral/cody/problems/3009-test-driven-solution-probability-problem-3\"\u003eProbability Problem 3\u003c/a\u003e\u003c/p\u003e","function_template":"function vec = fcn(len)\r\n  vec = nan(len, 1);\r\nend","test_suite":"%%\r\n% test for correct size\r\nfor iter = 1:10\r\n  vectorLength = randi([1 100]);\r\n  result       = fcn(vectorLength);\r\n  assert(isequal([vectorLength, 1], size(result)));\r\nend\r\n\r\n%%\r\n% get large sample\r\nvectorLength = 10000;\r\nresult       = fcn(vectorLength);\r\n\r\n% build empirical cumulative distribution function\r\nxEmpirical = sort(result);                       % x-axis\r\nyEmpirical = (1:vectorLength).' ./ vectorLength; % y-axis\r\n\r\n% build theoretical cumulative distribution function\r\nxTheoretical = xEmpirical; % x-axis\r\nerfInput     = sqrt(0.5) / pi * (xTheoretical - exp(1));\r\nyTheoretical = 0.5*erf(erfInput) + 0.5; % y-axis\r\n\r\n% compute statistics on diff between empirical and theoretical\r\nerrorList = abs(yEmpirical - yTheoretical);\r\nerrorMax  = max(errorList);\r\nerrorSum  = sum(errorList);\r\nerrorStd  = std(errorList);\r\n\r\n% if fcn is correct, this should pass at least 99.9% of the time\r\nassert(errorMax \u003c .02);\r\nassert(errorSum \u003e 10.1);\r\nassert(errorStd \u003e .00075);","published":true,"deleted":false,"likes_count":1,"comments_count":0,"created_by":692,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":15,"test_suite_updated_at":"2015-02-11T19:01:30.000Z","rescore_all_solutions":false,"group_id":1,"created_at":"2015-02-11T17:31:57.000Z","updated_at":"2025-11-21T18:40:33.000Z","published_at":"2015-02-11T17:33:58.000Z","restored_at":null,"restored_by":null,"spam":false,"simulink":false,"admin_reviewed":false,"description_opc":"{\"relationships\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/document\",\"targetMode\":\"\",\"relationshipId\":\"rId1\",\"target\":\"/matlab/document.xml\"},{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/output\",\"targetMode\":\"\",\"relationshipId\":\"rId2\",\"target\":\"/matlab/output.xml\"}],\"parts\":[{\"partUri\":\"/matlab/document.xml\",\"relationship\":[],\"contentType\":\"application/vnd.mathworks.matlab.code.document+xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\"?\u003e\\n\u003cw:document xmlns:w=\\\"http://schemas.openxmlformats.org/wordprocessingml/2006/main\\\"\u003e\u003cw:body\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:rPr\u003e\u003cw:b/\u003e\u003c/w:rPr\u003e\u003cw:t\u003eProblem:\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e Without any Cody cheats, write code that passes the test suite.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:rPr\u003e\u003cw:b/\u003e\u003c/w:rPr\u003e\u003cw:t\u003eHint:\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e The test suite gets samples from the probability distribution represented by your code. A cumulative distribution function is then built from the samples. This is the empirical distribution, which is compared against the theoretical distribution you must infer from the test suite.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:rPr\u003e\u003cw:b/\u003e\u003c/w:rPr\u003e\u003cw:t\u003eSee also:\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=\\\"http://en.wikipedia.org/wiki/Cumulative_distribution_function\\\"\u003e\u003cw:r\u003e\u003cw:t\u003eCumulative Distribution Function\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\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:rPr\u003e\u003cw:b/\u003e\u003c/w:rPr\u003e\u003cw:t\u003eProblems in Series:\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=\\\"http://www.mathworks.com/matlabcentral/cody/problems/2995-test-driven-solution-probability-problem-1\\\"\u003e\u003cw:r\u003e\u003cw:t\u003eProbability Problem 1\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:hyperlink\u003e\u003cw:r\u003e\u003cw:t\u003e,\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=\\\"http://www.mathworks.com/matlabcentral/cody/problems/3009-test-driven-solution-probability-problem-3\\\"\u003e\u003cw:r\u003e\u003cw:t\u003eProbability Problem 3\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:hyperlink\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":2995,"title":"Test Driven Solution - Probability Problem 1","description":"*Problem:* Without any Cody cheats, write code that passes the test suite.\r\n\r\n*Hint:* The test suite gets samples from the probability distribution represented by your code.  A cumulative distribution function is then built from the samples.  This is the empirical distribution, which is compared against the theoretical distribution you must infer from the test suite.\r\n\r\n*See also:* \u003chttp://en.wikipedia.org/wiki/Cumulative_distribution_function Cumulative Distribution Function\u003e\r\n\r\n*Problems in Series:* \u003chttp://www.mathworks.com/matlabcentral/cody/problems/3006-test-driven-solution-probability-problem-2 Probability Problem 2\u003e, \u003chttp://www.mathworks.com/matlabcentral/cody/problems/3009-test-driven-solution-probability-problem-3 Probability Problem 3\u003e","description_html":"\u003cp\u003e\u003cb\u003eProblem:\u003c/b\u003e Without any Cody cheats, write code that passes the test suite.\u003c/p\u003e\u003cp\u003e\u003cb\u003eHint:\u003c/b\u003e The test suite gets samples from the probability distribution represented by your code.  A cumulative distribution function is then built from the samples.  This is the empirical distribution, which is compared against the theoretical distribution you must infer from the test suite.\u003c/p\u003e\u003cp\u003e\u003cb\u003eSee also:\u003c/b\u003e \u003ca href = \"http://en.wikipedia.org/wiki/Cumulative_distribution_function\"\u003eCumulative Distribution Function\u003c/a\u003e\u003c/p\u003e\u003cp\u003e\u003cb\u003eProblems in Series:\u003c/b\u003e \u003ca href = \"http://www.mathworks.com/matlabcentral/cody/problems/3006-test-driven-solution-probability-problem-2\"\u003eProbability Problem 2\u003c/a\u003e, \u003ca href = \"http://www.mathworks.com/matlabcentral/cody/problems/3009-test-driven-solution-probability-problem-3\"\u003eProbability Problem 3\u003c/a\u003e\u003c/p\u003e","function_template":"function vec = fcn(len)\r\n  vec = nan(len, 1);\r\nend","test_suite":"%%\r\n% test for correct size\r\nfor iter = 1:10\r\n  vectorLength = randi([1 100]);\r\n  result       = fcn(vectorLength);\r\n  assert(isequal([vectorLength, 1], size(result)));\r\nend\r\n\r\n%%\r\n% get large sample\r\nvectorLength = 10000;\r\nresult       = fcn(vectorLength);\r\n\r\n% build empirical cumulative distribution function\r\nxEmpirical = sort(result);                       % x-axis\r\nyEmpirical = (1:vectorLength).' ./ vectorLength; % y-axis\r\n\r\n% build theoretical cumulative distribution function\r\nxTheoretical = xEmpirical;       % x-axis\r\nyTheoretical = 0.5*xTheoretical; % y-axis\r\n\r\n% compute statistics on diff between empirical and theoretical\r\nerrorList = abs(yEmpirical - yTheoretical);\r\nerrorMax  = max(errorList);\r\nerrorMean = mean(errorList);\r\nerrorStd  = std(errorList);\r\n      \r\n% if fcn is correct, this should pass at least 99.9% of the time\r\nassert(errorMax  \u003c .02);\r\nassert(errorMean \u003c .012);\r\nassert(errorMean \u003e .0008);\r\nassert(errorStd  \u003e .0007);","published":true,"deleted":false,"likes_count":1,"comments_count":2,"created_by":692,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":18,"test_suite_updated_at":"2015-02-12T17:42:40.000Z","rescore_all_solutions":false,"group_id":1,"created_at":"2015-02-10T14:53:38.000Z","updated_at":"2025-11-21T18:53:27.000Z","published_at":"2015-02-10T15:01:03.000Z","restored_at":null,"restored_by":null,"spam":false,"simulink":false,"admin_reviewed":false,"description_opc":"{\"relationships\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/document\",\"targetMode\":\"\",\"relationshipId\":\"rId1\",\"target\":\"/matlab/document.xml\"},{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/output\",\"targetMode\":\"\",\"relationshipId\":\"rId2\",\"target\":\"/matlab/output.xml\"}],\"parts\":[{\"partUri\":\"/matlab/document.xml\",\"relationship\":[],\"contentType\":\"application/vnd.mathworks.matlab.code.document+xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\"?\u003e\\n\u003cw:document xmlns:w=\\\"http://schemas.openxmlformats.org/wordprocessingml/2006/main\\\"\u003e\u003cw:body\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:rPr\u003e\u003cw:b/\u003e\u003c/w:rPr\u003e\u003cw:t\u003eProblem:\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e Without any Cody cheats, write code that passes the test suite.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:rPr\u003e\u003cw:b/\u003e\u003c/w:rPr\u003e\u003cw:t\u003eHint:\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e The test suite gets samples from the probability distribution represented by your code. A cumulative distribution function is then built from the samples. This is the empirical distribution, which is compared against the theoretical distribution you must infer from the test suite.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:rPr\u003e\u003cw:b/\u003e\u003c/w:rPr\u003e\u003cw:t\u003eSee also:\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=\\\"http://en.wikipedia.org/wiki/Cumulative_distribution_function\\\"\u003e\u003cw:r\u003e\u003cw:t\u003eCumulative Distribution Function\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\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:rPr\u003e\u003cw:b/\u003e\u003c/w:rPr\u003e\u003cw:t\u003eProblems in Series:\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=\\\"http://www.mathworks.com/matlabcentral/cody/problems/3006-test-driven-solution-probability-problem-2\\\"\u003e\u003cw:r\u003e\u003cw:t\u003eProbability Problem 2\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:hyperlink\u003e\u003cw:r\u003e\u003cw:t\u003e,\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=\\\"http://www.mathworks.com/matlabcentral/cody/problems/3009-test-driven-solution-probability-problem-3\\\"\u003e\u003cw:r\u003e\u003cw:t\u003eProbability Problem 3\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:hyperlink\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":3009,"title":"Test Driven Solution - Probability Problem 3","description":"*Problem:* Without any Cody cheats, write code that passes the test suite.\r\n\r\n*Hint:* The test suite gets samples from the probability distribution represented by your code.  A cumulative distribution function is then built from the samples.  This is the empirical distribution, which is compared against the theoretical distribution you must infer from the test suite.\r\n\r\n*See also:* \u003chttp://en.wikipedia.org/wiki/Cumulative_distribution_function Cumulative Distribution Function\u003e\r\n\r\n*Problems in Series:* \u003chttp://www.mathworks.com/matlabcentral/cody/problems/2995-test-driven-solution-probability-problem-1 Probability Problem 1\u003e, \u003chttp://www.mathworks.com/matlabcentral/cody/problems/3006-test-driven-solution-probability-problem-2 Probability Problem 2\u003e","description_html":"\u003cp\u003e\u003cb\u003eProblem:\u003c/b\u003e Without any Cody cheats, write code that passes the test suite.\u003c/p\u003e\u003cp\u003e\u003cb\u003eHint:\u003c/b\u003e The test suite gets samples from the probability distribution represented by your code.  A cumulative distribution function is then built from the samples.  This is the empirical distribution, which is compared against the theoretical distribution you must infer from the test suite.\u003c/p\u003e\u003cp\u003e\u003cb\u003eSee also:\u003c/b\u003e \u003ca href = \"http://en.wikipedia.org/wiki/Cumulative_distribution_function\"\u003eCumulative Distribution Function\u003c/a\u003e\u003c/p\u003e\u003cp\u003e\u003cb\u003eProblems in Series:\u003c/b\u003e \u003ca href = \"http://www.mathworks.com/matlabcentral/cody/problems/2995-test-driven-solution-probability-problem-1\"\u003eProbability Problem 1\u003c/a\u003e, \u003ca href = \"http://www.mathworks.com/matlabcentral/cody/problems/3006-test-driven-solution-probability-problem-2\"\u003eProbability Problem 2\u003c/a\u003e\u003c/p\u003e","function_template":"function vec = fcn(len)\r\n  vec = nan(len, 1);\r\nend","test_suite":"%%\r\n% test for correct size\r\nfor iter = 1:10\r\n  vectorLength = randi([1 100]);\r\n  result       = fcn(vectorLength);\r\n  assert(isequal([vectorLength, 1], size(result)));\r\nend\r\n\r\n%%\r\n% get large sample\r\nvectorLength = 10000;\r\nresult       = fcn(vectorLength);\r\n\r\n% built empirical cumulative distribution function\r\nxEmpirical = 0:10;                     % x-axis\r\ncounts     = accumarray(result+1, 1);\r\ndensity    = counts ./ sum(counts);\r\nyEmpirical = cumsum(density);          % y-axis\r\n\r\n% build theoretical cumulative distribution function\r\nxTheoretical = xEmpirical; % x-axis\r\nfor k = xTheoretical\r\n  yTheoretical(k+1, 1) = betainc(exp(-1), 10-k, k+1); % y-axis\r\nend\r\n\r\n% compute statistics on diff between empirical and theoretical\r\nerrorList = abs(yEmpirical - yTheoretical);\r\nerrorMax  = max(errorList);\r\nerrorSum  = sum(errorList);\r\nerrorStd  = std(errorList);\r\n\r\n% if fcn is correct, this should pass at least 99.9% of the time\r\nassert(errorMax \u003c .018);\r\nassert(errorSum \u003e .0045);\r\nassert(errorStd \u003e .0004);","published":true,"deleted":false,"likes_count":2,"comments_count":0,"created_by":692,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":12,"test_suite_updated_at":null,"rescore_all_solutions":false,"group_id":1,"created_at":"2015-02-12T17:08:10.000Z","updated_at":"2025-10-20T15:59:08.000Z","published_at":"2015-02-12T17:08:43.000Z","restored_at":null,"restored_by":null,"spam":false,"simulink":false,"admin_reviewed":false,"description_opc":"{\"relationships\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/document\",\"targetMode\":\"\",\"relationshipId\":\"rId1\",\"target\":\"/matlab/document.xml\"},{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/output\",\"targetMode\":\"\",\"relationshipId\":\"rId2\",\"target\":\"/matlab/output.xml\"}],\"parts\":[{\"partUri\":\"/matlab/document.xml\",\"relationship\":[],\"contentType\":\"application/vnd.mathworks.matlab.code.document+xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\"?\u003e\\n\u003cw:document xmlns:w=\\\"http://schemas.openxmlformats.org/wordprocessingml/2006/main\\\"\u003e\u003cw:body\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:rPr\u003e\u003cw:b/\u003e\u003c/w:rPr\u003e\u003cw:t\u003eProblem:\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e Without any Cody cheats, write code that passes the test suite.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:rPr\u003e\u003cw:b/\u003e\u003c/w:rPr\u003e\u003cw:t\u003eHint:\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e The test suite gets samples from the probability distribution represented by your code. A cumulative distribution function is then built from the samples. This is the empirical distribution, which is compared against the theoretical distribution you must infer from the test suite.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:rPr\u003e\u003cw:b/\u003e\u003c/w:rPr\u003e\u003cw:t\u003eSee also:\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=\\\"http://en.wikipedia.org/wiki/Cumulative_distribution_function\\\"\u003e\u003cw:r\u003e\u003cw:t\u003eCumulative Distribution Function\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\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:rPr\u003e\u003cw:b/\u003e\u003c/w:rPr\u003e\u003cw:t\u003eProblems in Series:\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=\\\"http://www.mathworks.com/matlabcentral/cody/problems/2995-test-driven-solution-probability-problem-1\\\"\u003e\u003cw:r\u003e\u003cw:t\u003eProbability Problem 1\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:hyperlink\u003e\u003cw:r\u003e\u003cw:t\u003e,\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=\\\"http://www.mathworks.com/matlabcentral/cody/problems/3006-test-driven-solution-probability-problem-2\\\"\u003e\u003cw:r\u003e\u003cw:t\u003eProbability Problem 2\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:hyperlink\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":3006,"title":"Test Driven Solution - Probability Problem 2","description":"*Problem:* Without any Cody cheats, write code that passes the test suite.\r\n\r\n*Hint:* The test suite gets samples from the probability distribution represented by your code.  A cumulative distribution function is then built from the samples.  This is the empirical distribution, which is compared against the theoretical distribution you must infer from the test suite.\r\n\r\n*See also:* \u003chttp://en.wikipedia.org/wiki/Cumulative_distribution_function Cumulative Distribution Function\u003e\r\n\r\n*Problems in Series:* \u003chttp://www.mathworks.com/matlabcentral/cody/problems/2995-test-driven-solution-probability-problem-1 Probability Problem 1\u003e, \u003chttp://www.mathworks.com/matlabcentral/cody/problems/3009-test-driven-solution-probability-problem-3 Probability Problem 3\u003e","description_html":"\u003cp\u003e\u003cb\u003eProblem:\u003c/b\u003e Without any Cody cheats, write code that passes the test suite.\u003c/p\u003e\u003cp\u003e\u003cb\u003eHint:\u003c/b\u003e The test suite gets samples from the probability distribution represented by your code.  A cumulative distribution function is then built from the samples.  This is the empirical distribution, which is compared against the theoretical distribution you must infer from the test suite.\u003c/p\u003e\u003cp\u003e\u003cb\u003eSee also:\u003c/b\u003e \u003ca href = \"http://en.wikipedia.org/wiki/Cumulative_distribution_function\"\u003eCumulative Distribution Function\u003c/a\u003e\u003c/p\u003e\u003cp\u003e\u003cb\u003eProblems in Series:\u003c/b\u003e \u003ca href = \"http://www.mathworks.com/matlabcentral/cody/problems/2995-test-driven-solution-probability-problem-1\"\u003eProbability Problem 1\u003c/a\u003e, \u003ca href = \"http://www.mathworks.com/matlabcentral/cody/problems/3009-test-driven-solution-probability-problem-3\"\u003eProbability Problem 3\u003c/a\u003e\u003c/p\u003e","function_template":"function vec = fcn(len)\r\n  vec = nan(len, 1);\r\nend","test_suite":"%%\r\n% test for correct size\r\nfor iter = 1:10\r\n  vectorLength = randi([1 100]);\r\n  result       = fcn(vectorLength);\r\n  assert(isequal([vectorLength, 1], size(result)));\r\nend\r\n\r\n%%\r\n% get large sample\r\nvectorLength = 10000;\r\nresult       = fcn(vectorLength);\r\n\r\n% build empirical cumulative distribution function\r\nxEmpirical = sort(result);                       % x-axis\r\nyEmpirical = (1:vectorLength).' ./ vectorLength; % y-axis\r\n\r\n% build theoretical cumulative distribution function\r\nxTheoretical = xEmpirical; % x-axis\r\nerfInput     = sqrt(0.5) / pi * (xTheoretical - exp(1));\r\nyTheoretical = 0.5*erf(erfInput) + 0.5; % y-axis\r\n\r\n% compute statistics on diff between empirical and theoretical\r\nerrorList = abs(yEmpirical - yTheoretical);\r\nerrorMax  = max(errorList);\r\nerrorSum  = sum(errorList);\r\nerrorStd  = std(errorList);\r\n\r\n% if fcn is correct, this should pass at least 99.9% of the time\r\nassert(errorMax \u003c .02);\r\nassert(errorSum \u003e 10.1);\r\nassert(errorStd \u003e .00075);","published":true,"deleted":false,"likes_count":1,"comments_count":0,"created_by":692,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":15,"test_suite_updated_at":"2015-02-11T19:01:30.000Z","rescore_all_solutions":false,"group_id":1,"created_at":"2015-02-11T17:31:57.000Z","updated_at":"2025-11-21T18:40:33.000Z","published_at":"2015-02-11T17:33:58.000Z","restored_at":null,"restored_by":null,"spam":false,"simulink":false,"admin_reviewed":false,"description_opc":"{\"relationships\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/document\",\"targetMode\":\"\",\"relationshipId\":\"rId1\",\"target\":\"/matlab/document.xml\"},{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/output\",\"targetMode\":\"\",\"relationshipId\":\"rId2\",\"target\":\"/matlab/output.xml\"}],\"parts\":[{\"partUri\":\"/matlab/document.xml\",\"relationship\":[],\"contentType\":\"application/vnd.mathworks.matlab.code.document+xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\"?\u003e\\n\u003cw:document xmlns:w=\\\"http://schemas.openxmlformats.org/wordprocessingml/2006/main\\\"\u003e\u003cw:body\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:rPr\u003e\u003cw:b/\u003e\u003c/w:rPr\u003e\u003cw:t\u003eProblem:\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e Without any Cody cheats, write code that passes the test suite.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:rPr\u003e\u003cw:b/\u003e\u003c/w:rPr\u003e\u003cw:t\u003eHint:\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e The test suite gets samples from the probability distribution represented by your code. A cumulative distribution function is then built from the samples. This is the empirical distribution, which is compared against the theoretical distribution you must infer from the test suite.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:rPr\u003e\u003cw:b/\u003e\u003c/w:rPr\u003e\u003cw:t\u003eSee also:\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=\\\"http://en.wikipedia.org/wiki/Cumulative_distribution_function\\\"\u003e\u003cw:r\u003e\u003cw:t\u003eCumulative Distribution Function\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\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:rPr\u003e\u003cw:b/\u003e\u003c/w:rPr\u003e\u003cw:t\u003eProblems in Series:\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=\\\"http://www.mathworks.com/matlabcentral/cody/problems/2995-test-driven-solution-probability-problem-1\\\"\u003e\u003cw:r\u003e\u003cw:t\u003eProbability Problem 1\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:hyperlink\u003e\u003cw:r\u003e\u003cw:t\u003e,\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=\\\"http://www.mathworks.com/matlabcentral/cody/problems/3009-test-driven-solution-probability-problem-3\\\"\u003e\u003cw:r\u003e\u003cw:t\u003eProbability Problem 3\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:hyperlink\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":2995,"title":"Test Driven Solution - Probability Problem 1","description":"*Problem:* Without any Cody cheats, write code that passes the test suite.\r\n\r\n*Hint:* The test suite gets samples from the probability distribution represented by your code.  A cumulative distribution function is then built from the samples.  This is the empirical distribution, which is compared against the theoretical distribution you must infer from the test suite.\r\n\r\n*See also:* \u003chttp://en.wikipedia.org/wiki/Cumulative_distribution_function Cumulative Distribution Function\u003e\r\n\r\n*Problems in Series:* \u003chttp://www.mathworks.com/matlabcentral/cody/problems/3006-test-driven-solution-probability-problem-2 Probability Problem 2\u003e, \u003chttp://www.mathworks.com/matlabcentral/cody/problems/3009-test-driven-solution-probability-problem-3 Probability Problem 3\u003e","description_html":"\u003cp\u003e\u003cb\u003eProblem:\u003c/b\u003e Without any Cody cheats, write code that passes the test suite.\u003c/p\u003e\u003cp\u003e\u003cb\u003eHint:\u003c/b\u003e The test suite gets samples from the probability distribution represented by your code.  A cumulative distribution function is then built from the samples.  This is the empirical distribution, which is compared against the theoretical distribution you must infer from the test suite.\u003c/p\u003e\u003cp\u003e\u003cb\u003eSee also:\u003c/b\u003e \u003ca href = \"http://en.wikipedia.org/wiki/Cumulative_distribution_function\"\u003eCumulative Distribution Function\u003c/a\u003e\u003c/p\u003e\u003cp\u003e\u003cb\u003eProblems in Series:\u003c/b\u003e \u003ca href = \"http://www.mathworks.com/matlabcentral/cody/problems/3006-test-driven-solution-probability-problem-2\"\u003eProbability Problem 2\u003c/a\u003e, \u003ca href = \"http://www.mathworks.com/matlabcentral/cody/problems/3009-test-driven-solution-probability-problem-3\"\u003eProbability Problem 3\u003c/a\u003e\u003c/p\u003e","function_template":"function vec = fcn(len)\r\n  vec = nan(len, 1);\r\nend","test_suite":"%%\r\n% test for correct size\r\nfor iter = 1:10\r\n  vectorLength = randi([1 100]);\r\n  result       = fcn(vectorLength);\r\n  assert(isequal([vectorLength, 1], size(result)));\r\nend\r\n\r\n%%\r\n% get large sample\r\nvectorLength = 10000;\r\nresult       = fcn(vectorLength);\r\n\r\n% build empirical cumulative distribution function\r\nxEmpirical = sort(result);                       % x-axis\r\nyEmpirical = (1:vectorLength).' ./ vectorLength; % y-axis\r\n\r\n% build theoretical cumulative distribution function\r\nxTheoretical = xEmpirical;       % x-axis\r\nyTheoretical = 0.5*xTheoretical; % y-axis\r\n\r\n% compute statistics on diff between empirical and theoretical\r\nerrorList = abs(yEmpirical - yTheoretical);\r\nerrorMax  = max(errorList);\r\nerrorMean = mean(errorList);\r\nerrorStd  = std(errorList);\r\n      \r\n% if fcn is correct, this should pass at least 99.9% of the time\r\nassert(errorMax  \u003c .02);\r\nassert(errorMean \u003c .012);\r\nassert(errorMean \u003e .0008);\r\nassert(errorStd  \u003e .0007);","published":true,"deleted":false,"likes_count":1,"comments_count":2,"created_by":692,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":18,"test_suite_updated_at":"2015-02-12T17:42:40.000Z","rescore_all_solutions":false,"group_id":1,"created_at":"2015-02-10T14:53:38.000Z","updated_at":"2025-11-21T18:53:27.000Z","published_at":"2015-02-10T15:01:03.000Z","restored_at":null,"restored_by":null,"spam":false,"simulink":false,"admin_reviewed":false,"description_opc":"{\"relationships\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/document\",\"targetMode\":\"\",\"relationshipId\":\"rId1\",\"target\":\"/matlab/document.xml\"},{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/output\",\"targetMode\":\"\",\"relationshipId\":\"rId2\",\"target\":\"/matlab/output.xml\"}],\"parts\":[{\"partUri\":\"/matlab/document.xml\",\"relationship\":[],\"contentType\":\"application/vnd.mathworks.matlab.code.document+xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\"?\u003e\\n\u003cw:document xmlns:w=\\\"http://schemas.openxmlformats.org/wordprocessingml/2006/main\\\"\u003e\u003cw:body\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:rPr\u003e\u003cw:b/\u003e\u003c/w:rPr\u003e\u003cw:t\u003eProblem:\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e Without any Cody cheats, write code that passes the test suite.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:rPr\u003e\u003cw:b/\u003e\u003c/w:rPr\u003e\u003cw:t\u003eHint:\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e The test suite gets samples from the probability distribution represented by your code. A cumulative distribution function is then built from the samples. This is the empirical distribution, which is compared against the theoretical distribution you must infer from the test suite.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:rPr\u003e\u003cw:b/\u003e\u003c/w:rPr\u003e\u003cw:t\u003eSee also:\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=\\\"http://en.wikipedia.org/wiki/Cumulative_distribution_function\\\"\u003e\u003cw:r\u003e\u003cw:t\u003eCumulative Distribution Function\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\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:rPr\u003e\u003cw:b/\u003e\u003c/w:rPr\u003e\u003cw:t\u003eProblems in Series:\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=\\\"http://www.mathworks.com/matlabcentral/cody/problems/3006-test-driven-solution-probability-problem-2\\\"\u003e\u003cw:r\u003e\u003cw:t\u003eProbability Problem 2\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:hyperlink\u003e\u003cw:r\u003e\u003cw:t\u003e,\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=\\\"http://www.mathworks.com/matlabcentral/cody/problems/3009-test-driven-solution-probability-problem-3\\\"\u003e\u003cw:r\u003e\u003cw:t\u003eProbability Problem 3\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:hyperlink\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":3009,"title":"Test Driven Solution - Probability Problem 3","description":"*Problem:* Without any Cody cheats, write code that passes the test suite.\r\n\r\n*Hint:* The test suite gets samples from the probability distribution represented by your code.  A cumulative distribution function is then built from the samples.  This is the empirical distribution, which is compared against the theoretical distribution you must infer from the test suite.\r\n\r\n*See also:* \u003chttp://en.wikipedia.org/wiki/Cumulative_distribution_function Cumulative Distribution Function\u003e\r\n\r\n*Problems in Series:* \u003chttp://www.mathworks.com/matlabcentral/cody/problems/2995-test-driven-solution-probability-problem-1 Probability Problem 1\u003e, \u003chttp://www.mathworks.com/matlabcentral/cody/problems/3006-test-driven-solution-probability-problem-2 Probability Problem 2\u003e","description_html":"\u003cp\u003e\u003cb\u003eProblem:\u003c/b\u003e Without any Cody cheats, write code that passes the test suite.\u003c/p\u003e\u003cp\u003e\u003cb\u003eHint:\u003c/b\u003e The test suite gets samples from the probability distribution represented by your code.  A cumulative distribution function is then built from the samples.  This is the empirical distribution, which is compared against the theoretical distribution you must infer from the test suite.\u003c/p\u003e\u003cp\u003e\u003cb\u003eSee also:\u003c/b\u003e \u003ca href = \"http://en.wikipedia.org/wiki/Cumulative_distribution_function\"\u003eCumulative Distribution Function\u003c/a\u003e\u003c/p\u003e\u003cp\u003e\u003cb\u003eProblems in Series:\u003c/b\u003e \u003ca href = \"http://www.mathworks.com/matlabcentral/cody/problems/2995-test-driven-solution-probability-problem-1\"\u003eProbability Problem 1\u003c/a\u003e, \u003ca href = \"http://www.mathworks.com/matlabcentral/cody/problems/3006-test-driven-solution-probability-problem-2\"\u003eProbability Problem 2\u003c/a\u003e\u003c/p\u003e","function_template":"function vec = fcn(len)\r\n  vec = nan(len, 1);\r\nend","test_suite":"%%\r\n% test for correct size\r\nfor iter = 1:10\r\n  vectorLength = randi([1 100]);\r\n  result       = fcn(vectorLength);\r\n  assert(isequal([vectorLength, 1], size(result)));\r\nend\r\n\r\n%%\r\n% get large sample\r\nvectorLength = 10000;\r\nresult       = fcn(vectorLength);\r\n\r\n% built empirical cumulative distribution function\r\nxEmpirical = 0:10;                     % x-axis\r\ncounts     = accumarray(result+1, 1);\r\ndensity    = counts ./ sum(counts);\r\nyEmpirical = cumsum(density);          % y-axis\r\n\r\n% build theoretical cumulative distribution function\r\nxTheoretical = xEmpirical; % x-axis\r\nfor k = xTheoretical\r\n  yTheoretical(k+1, 1) = betainc(exp(-1), 10-k, k+1); % y-axis\r\nend\r\n\r\n% compute statistics on diff between empirical and theoretical\r\nerrorList = abs(yEmpirical - yTheoretical);\r\nerrorMax  = max(errorList);\r\nerrorSum  = sum(errorList);\r\nerrorStd  = std(errorList);\r\n\r\n% if fcn is correct, this should pass at least 99.9% of the time\r\nassert(errorMax \u003c .018);\r\nassert(errorSum \u003e .0045);\r\nassert(errorStd \u003e .0004);","published":true,"deleted":false,"likes_count":2,"comments_count":0,"created_by":692,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":12,"test_suite_updated_at":null,"rescore_all_solutions":false,"group_id":1,"created_at":"2015-02-12T17:08:10.000Z","updated_at":"2025-10-20T15:59:08.000Z","published_at":"2015-02-12T17:08:43.000Z","restored_at":null,"restored_by":null,"spam":false,"simulink":false,"admin_reviewed":false,"description_opc":"{\"relationships\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/document\",\"targetMode\":\"\",\"relationshipId\":\"rId1\",\"target\":\"/matlab/document.xml\"},{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/output\",\"targetMode\":\"\",\"relationshipId\":\"rId2\",\"target\":\"/matlab/output.xml\"}],\"parts\":[{\"partUri\":\"/matlab/document.xml\",\"relationship\":[],\"contentType\":\"application/vnd.mathworks.matlab.code.document+xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\"?\u003e\\n\u003cw:document xmlns:w=\\\"http://schemas.openxmlformats.org/wordprocessingml/2006/main\\\"\u003e\u003cw:body\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:rPr\u003e\u003cw:b/\u003e\u003c/w:rPr\u003e\u003cw:t\u003eProblem:\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e Without any Cody cheats, write code that passes the test suite.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:rPr\u003e\u003cw:b/\u003e\u003c/w:rPr\u003e\u003cw:t\u003eHint:\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e The test suite gets samples from the probability distribution represented by your code. A cumulative distribution function is then built from the samples. This is the empirical distribution, which is compared against the theoretical distribution you must infer from the test suite.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:rPr\u003e\u003cw:b/\u003e\u003c/w:rPr\u003e\u003cw:t\u003eSee also:\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=\\\"http://en.wikipedia.org/wiki/Cumulative_distribution_function\\\"\u003e\u003cw:r\u003e\u003cw:t\u003eCumulative Distribution Function\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\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:rPr\u003e\u003cw:b/\u003e\u003c/w:rPr\u003e\u003cw:t\u003eProblems in Series:\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=\\\"http://www.mathworks.com/matlabcentral/cody/problems/2995-test-driven-solution-probability-problem-1\\\"\u003e\u003cw:r\u003e\u003cw:t\u003eProbability Problem 1\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:hyperlink\u003e\u003cw:r\u003e\u003cw:t\u003e,\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=\\\"http://www.mathworks.com/matlabcentral/cody/problems/3006-test-driven-solution-probability-problem-2\\\"\u003e\u003cw:r\u003e\u003cw:t\u003eProbability Problem 2\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:hyperlink\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\\\" 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