{"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":2805,"title":"Radiation Heat Transfer — View Factors (1)","description":"View factors (aka configuration factors) are utilized in some radiation heat transfer models to estimate heat transfer rates between surfaces. In particular, the thermal energy leaving a given surface is applied to other surfaces, as appropriate, based on how much the hot surface \"sees\" the other surfaces. As such, view factors are purely geometrical in nature. A range of view factor formulae are available \u003chttp://www.thermalradiation.net/tablecon.html here\u003e.\r\n\r\nFor this problem, calculate the view factor from surface 1 to surface 2 (F_1-2) for two directly opposed, infinitely long plates of the same finite width given the height, which may be a vector of values:\r\n\r\n\u003c\u003chttp://www.thermalradiation.net/images/C-1fig.gif\u003e\u003e\r\n\r\n\u003c\u003chttp://www.thermalradiation.net/images/C-1eq.gif\u003e\u003e","description_html":"\u003cp\u003eView factors (aka configuration factors) are utilized in some radiation heat transfer models to estimate heat transfer rates between surfaces. In particular, the thermal energy leaving a given surface is applied to other surfaces, as appropriate, based on how much the hot surface \"sees\" the other surfaces. As such, view factors are purely geometrical in nature. A range of view factor formulae are available \u003ca href = \"http://www.thermalradiation.net/tablecon.html\"\u003ehere\u003c/a\u003e.\u003c/p\u003e\u003cp\u003eFor this problem, calculate the view factor from surface 1 to surface 2 (F_1-2) for two directly opposed, infinitely long plates of the same finite width given the height, which may be a vector of values:\u003c/p\u003e\u003cimg src = \"http://www.thermalradiation.net/images/C-1fig.gif\"\u003e\u003cimg src = \"http://www.thermalradiation.net/images/C-1eq.gif\"\u003e","function_template":"function F = view_factor(H)\r\n  F = 1;\r\nend","test_suite":"%%\r\nH = 1;\r\ny_correct = sqrt(2) - 1;\r\nassert(isequal(view_factor(H),y_correct))\r\n\r\n%%\r\nH = 3;\r\ny_correct = sqrt(10) - 3;\r\nassert(isequal(view_factor(H),y_correct))\r\n\r\n%%\r\nH = [0.5 2 4 10];\r\ny_correct = [sqrt(1.25)-0.5, sqrt(5)-2, sqrt(17)-4, sqrt(101)-10];\r\nassert(isequal(view_factor(H),y_correct))","published":true,"deleted":false,"likes_count":6,"comments_count":3,"created_by":26769,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":194,"test_suite_updated_at":null,"rescore_all_solutions":false,"group_id":26,"created_at":"2014-12-31T02:15:48.000Z","updated_at":"2026-04-07T04:55:13.000Z","published_at":"2014-12-31T02:15:48.000Z","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\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/image\",\"targetMode\":\"\",\"relationshipId\":\"rId1\",\"target\":\"/media/image1.gif\"},{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/image\",\"targetMode\":\"\",\"relationshipId\":\"rId2\",\"target\":\"/media/image2.gif\"}],\"contentType\":\"application/vnd.mathworks.matlab.code.document+xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\"?\u003e\\n\u003cw:document xmlns:w=\\\"http://schemas.openxmlformats.org/wordprocessingml/2006/main\\\"\u003e\u003cw:body\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eView factors (aka configuration factors) are utilized in some radiation heat transfer models to estimate heat transfer rates between surfaces. In particular, the thermal energy leaving a given surface is applied to other surfaces, as appropriate, based on how much the hot surface \\\"sees\\\" the other surfaces. As such, view factors are purely geometrical in nature. 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parallel to plane?","description":"Given the coefficients of the equation which defines a plane as follows:\r\nax+by+cz=d, return a boolean indicating whether the 2nd input parameter, a vector with 3 elements, is parallel to this plane. 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The plane will not be parallel to the xy plane.\u003c/p\u003e","function_template":"function isparallel = parallel2plane(a,b,c,d,vec)\r\n  isparallel = false;\r\nend","test_suite":"%%\r\na = 1;\r\nb=  1;\r\nc=1;\r\nd=1969;\r\nvec=[1 1 1];\r\ny_correct = false;\r\nassert(isequal(parallel2plane(a,b,c,d,vec),y_correct))\r\n%%\r\na = 1;\r\nb=  1;\r\nc=1;\r\nd=1969;\r\nvec=[0 -1492 1492];\r\ny_correct = true;\r\nassert(isequal(parallel2plane(a,b,c,d,vec),y_correct))\r\n%%\r\na = 1;\r\nb=  2;\r\nc=3;\r\nd=1969;\r\nvec=[0 -1492 1492];\r\ny_correct = false;\r\nassert(isequal(parallel2plane(a,b,c,d,vec),y_correct))\r\n%%\r\na = 1;\r\nb=  2;\r\nc=3;\r\nd=1969;\r\nvec=[1 0 -1/3];\r\ny_correct = true;\r\nassert(isequal(parallel2plane(a,b,c,d,vec),y_correct))\r\n%%\r\na = 0;\r\nb=  5;\r\nc=7;\r\nd=1969;\r\nvec=[0 49 -35];\r\ny_correct = true;\r\nassert(isequal(parallel2plane(a,b,c,d,vec),y_correct))\r\n","published":true,"deleted":false,"likes_count":1,"comments_count":0,"created_by":20079,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":85,"test_suite_updated_at":null,"rescore_all_solutions":false,"group_id":26,"created_at":"2013-12-29T12:49:35.000Z","updated_at":"2026-04-01T15:37:05.000Z","published_at":"2013-12-29T12:49:35.000Z","restored_at":null,"restored_by":null,"spam":false,"simulink":false,"admin_reviewed":false,"description_opc":"{\"relationships\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/document\",\"relationshipId\":\"rId1\",\"target\":\"/matlab/document.xml\"},{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/output\",\"relationshipId\":\"rId2\",\"target\":\"/matlab/output.xml\"}],\"parts\":[{\"partUri\":\"/matlab/document.xml\",\"relationship\":[],\"contentType\":\"application/vnd.mathworks.matlab.code.document+xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\"?\u003e\u003cw:document xmlns:w=\\\"http://schemas.openxmlformats.org/wordprocessingml/2006/main\\\"\u003e\u003cw:body\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eGiven the coefficients of the equation which defines a plane as follows: ax+by+cz=d, return a boolean indicating whether the 2nd input parameter, a vector with 3 elements, is parallel to this plane. The plane will not be parallel to the xy plane.\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":2069,"title":"Parallel vectors","description":"Return true or false depending on whether 2 vectors are parallel or not. Vectors can be  2 or 3 dimensional. The origin is not considered to be a vector in this problem.\r\nVectors are row vectors.\r\n\r\nSo:\r\np1=[0 0 0]\r\np2=[1 2 3]\r\noutput = false\r\n\r\np1=[1 1];\r\np2=[4 4]\r\noutput =true\r\n\r\n","description_html":"\u003cp\u003eReturn true or false depending on whether 2 vectors are parallel or not. Vectors can be  2 or 3 dimensional. The origin is not considered to be a vector in this problem.\r\nVectors are row vectors.\u003c/p\u003e\u003cp\u003eSo:\r\np1=[0 0 0]\r\np2=[1 2 3]\r\noutput = false\u003c/p\u003e\u003cp\u003ep1=[1 1];\r\np2=[4 4]\r\noutput =true\u003c/p\u003e","function_template":"function y = isparallel(p1,p2)\r\n  y = x;\r\nend","test_suite":"%%\r\np1=[1 2 3];\r\np2=[2 4 6];\r\ny_correct = true;\r\nassert(isequal(isparallel(p1,p2),y_correct))\r\n%%\r\np1=[1 2 3];\r\np2=[2 5 6];\r\ny_correct = false;\r\nassert(isequal(isparallel(p1,p2),y_correct))\r\n%%\r\np1=[666 911];\r\np2=[0.1 0.1*911/666];\r\ny_correct = true;\r\nassert(isequal(isparallel(p1,p2),y_correct))\r\n\r\n%%\r\np1=[1 2 3];\r\np2=[0 0 0];\r\ny_correct = false;\r\nassert(isequal(isparallel(p1,p2),y_correct))\r\n","published":true,"deleted":false,"likes_count":2,"comments_count":0,"created_by":20079,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":152,"test_suite_updated_at":"2013-12-20T15:17:23.000Z","rescore_all_solutions":false,"group_id":26,"created_at":"2013-12-20T14:46:59.000Z","updated_at":"2026-04-01T15:38:18.000Z","published_at":"2013-12-20T15:17:23.000Z","restored_at":null,"restored_by":null,"spam":false,"simulink":false,"admin_reviewed":false,"description_opc":"{\"relationships\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/document\",\"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\u003eReturn true or false depending on whether 2 vectors are parallel or not. Vectors can be 2 or 3 dimensional. The origin is not considered to be a vector in this problem. Vectors are row vectors.\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\u003eSo: p1=[0 0 0] p2=[1 2 3] output = false\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\u003ep1=[1 1]; p2=[4 4] output =true\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":2805,"title":"Radiation Heat Transfer — View Factors (1)","description":"View factors (aka configuration factors) are utilized in some radiation heat transfer models to estimate heat transfer rates between surfaces. In particular, the thermal energy leaving a given surface is applied to other surfaces, as appropriate, based on how much the hot surface \"sees\" the other surfaces. As such, view factors are purely geometrical in nature. A range of view factor formulae are available \u003chttp://www.thermalradiation.net/tablecon.html here\u003e.\r\n\r\nFor this problem, calculate the view factor from surface 1 to surface 2 (F_1-2) for two directly opposed, infinitely long plates of the same finite width given the height, which may be a vector of values:\r\n\r\n\u003c\u003chttp://www.thermalradiation.net/images/C-1fig.gif\u003e\u003e\r\n\r\n\u003c\u003chttp://www.thermalradiation.net/images/C-1eq.gif\u003e\u003e","description_html":"\u003cp\u003eView factors (aka configuration factors) are utilized in some radiation heat transfer models to estimate heat transfer rates between surfaces. In particular, the thermal energy leaving a given surface is applied to other surfaces, as appropriate, based on how much the hot surface \"sees\" the other surfaces. As such, view factors are purely geometrical in nature. A range of view factor formulae are available \u003ca href = \"http://www.thermalradiation.net/tablecon.html\"\u003ehere\u003c/a\u003e.\u003c/p\u003e\u003cp\u003eFor this problem, calculate the view factor from surface 1 to surface 2 (F_1-2) for two directly opposed, infinitely long plates of the same finite width given the height, which may be a vector of values:\u003c/p\u003e\u003cimg src = \"http://www.thermalradiation.net/images/C-1fig.gif\"\u003e\u003cimg src = \"http://www.thermalradiation.net/images/C-1eq.gif\"\u003e","function_template":"function F = view_factor(H)\r\n  F = 1;\r\nend","test_suite":"%%\r\nH = 1;\r\ny_correct = sqrt(2) - 1;\r\nassert(isequal(view_factor(H),y_correct))\r\n\r\n%%\r\nH = 3;\r\ny_correct = sqrt(10) - 3;\r\nassert(isequal(view_factor(H),y_correct))\r\n\r\n%%\r\nH = [0.5 2 4 10];\r\ny_correct = [sqrt(1.25)-0.5, sqrt(5)-2, sqrt(17)-4, sqrt(101)-10];\r\nassert(isequal(view_factor(H),y_correct))","published":true,"deleted":false,"likes_count":6,"comments_count":3,"created_by":26769,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":194,"test_suite_updated_at":null,"rescore_all_solutions":false,"group_id":26,"created_at":"2014-12-31T02:15:48.000Z","updated_at":"2026-04-07T04:55:13.000Z","published_at":"2014-12-31T02:15:48.000Z","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\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/image\",\"targetMode\":\"\",\"relationshipId\":\"rId1\",\"target\":\"/media/image1.gif\"},{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/image\",\"targetMode\":\"\",\"relationshipId\":\"rId2\",\"target\":\"/media/image2.gif\"}],\"contentType\":\"application/vnd.mathworks.matlab.code.document+xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\"?\u003e\\n\u003cw:document xmlns:w=\\\"http://schemas.openxmlformats.org/wordprocessingml/2006/main\\\"\u003e\u003cw:body\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eView factors (aka configuration factors) are utilized in some radiation heat transfer models to estimate heat transfer rates between surfaces. In particular, the thermal energy leaving a given surface is applied to other surfaces, as appropriate, based on how much the hot surface \\\"sees\\\" the other surfaces. As such, view factors are purely geometrical in nature. A range of view factor formulae are available\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.thermalradiation.net/tablecon.html\\\"\u003e\u003cw:r\u003e\u003cw:t\u003ehere\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\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eFor this problem, calculate the view factor from surface 1 to surface 2 (F_1-2) for two directly opposed, infinitely long plates of the same finite width given the height, which may be a vector of values:\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:customXml w:element=\\\"image\\\"\u003e\u003cw:customXmlPr\u003e\u003cw:attr w:name=\\\"height\\\" 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parallel to plane?","description":"Given the coefficients of the equation which defines a plane as follows:\r\nax+by+cz=d, return a boolean indicating whether the 2nd input parameter, a vector with 3 elements, is parallel to this plane. The plane will not be parallel to the xy plane.","description_html":"\u003cp\u003eGiven the coefficients of the equation which defines a plane as follows:\r\nax+by+cz=d, return a boolean indicating whether the 2nd input parameter, a vector with 3 elements, is parallel to this plane. The plane will not be parallel to the xy plane.\u003c/p\u003e","function_template":"function isparallel = parallel2plane(a,b,c,d,vec)\r\n  isparallel = false;\r\nend","test_suite":"%%\r\na = 1;\r\nb=  1;\r\nc=1;\r\nd=1969;\r\nvec=[1 1 1];\r\ny_correct = false;\r\nassert(isequal(parallel2plane(a,b,c,d,vec),y_correct))\r\n%%\r\na = 1;\r\nb=  1;\r\nc=1;\r\nd=1969;\r\nvec=[0 -1492 1492];\r\ny_correct = true;\r\nassert(isequal(parallel2plane(a,b,c,d,vec),y_correct))\r\n%%\r\na = 1;\r\nb=  2;\r\nc=3;\r\nd=1969;\r\nvec=[0 -1492 1492];\r\ny_correct = false;\r\nassert(isequal(parallel2plane(a,b,c,d,vec),y_correct))\r\n%%\r\na = 1;\r\nb=  2;\r\nc=3;\r\nd=1969;\r\nvec=[1 0 -1/3];\r\ny_correct = true;\r\nassert(isequal(parallel2plane(a,b,c,d,vec),y_correct))\r\n%%\r\na = 0;\r\nb=  5;\r\nc=7;\r\nd=1969;\r\nvec=[0 49 -35];\r\ny_correct = true;\r\nassert(isequal(parallel2plane(a,b,c,d,vec),y_correct))\r\n","published":true,"deleted":false,"likes_count":1,"comments_count":0,"created_by":20079,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":85,"test_suite_updated_at":null,"rescore_all_solutions":false,"group_id":26,"created_at":"2013-12-29T12:49:35.000Z","updated_at":"2026-04-01T15:37:05.000Z","published_at":"2013-12-29T12:49:35.000Z","restored_at":null,"restored_by":null,"spam":false,"simulink":false,"admin_reviewed":false,"description_opc":"{\"relationships\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/document\",\"relationshipId\":\"rId1\",\"target\":\"/matlab/document.xml\"},{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/output\",\"relationshipId\":\"rId2\",\"target\":\"/matlab/output.xml\"}],\"parts\":[{\"partUri\":\"/matlab/document.xml\",\"relationship\":[],\"contentType\":\"application/vnd.mathworks.matlab.code.document+xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\"?\u003e\u003cw:document xmlns:w=\\\"http://schemas.openxmlformats.org/wordprocessingml/2006/main\\\"\u003e\u003cw:body\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eGiven the coefficients of the equation which defines a plane as follows: ax+by+cz=d, return a boolean indicating whether the 2nd input parameter, a vector with 3 elements, is parallel to this plane. The plane will not be parallel to the xy plane.\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":2069,"title":"Parallel vectors","description":"Return true or false depending on whether 2 vectors are parallel or not. Vectors can be  2 or 3 dimensional. The origin is not considered to be a vector in this problem.\r\nVectors are row vectors.\r\n\r\nSo:\r\np1=[0 0 0]\r\np2=[1 2 3]\r\noutput = false\r\n\r\np1=[1 1];\r\np2=[4 4]\r\noutput =true\r\n\r\n","description_html":"\u003cp\u003eReturn true or false depending on whether 2 vectors are parallel or not. Vectors can be  2 or 3 dimensional. The origin is not considered to be a vector in this problem.\r\nVectors are row vectors.\u003c/p\u003e\u003cp\u003eSo:\r\np1=[0 0 0]\r\np2=[1 2 3]\r\noutput = false\u003c/p\u003e\u003cp\u003ep1=[1 1];\r\np2=[4 4]\r\noutput =true\u003c/p\u003e","function_template":"function y = isparallel(p1,p2)\r\n  y = x;\r\nend","test_suite":"%%\r\np1=[1 2 3];\r\np2=[2 4 6];\r\ny_correct = true;\r\nassert(isequal(isparallel(p1,p2),y_correct))\r\n%%\r\np1=[1 2 3];\r\np2=[2 5 6];\r\ny_correct = false;\r\nassert(isequal(isparallel(p1,p2),y_correct))\r\n%%\r\np1=[666 911];\r\np2=[0.1 0.1*911/666];\r\ny_correct = true;\r\nassert(isequal(isparallel(p1,p2),y_correct))\r\n\r\n%%\r\np1=[1 2 3];\r\np2=[0 0 0];\r\ny_correct = false;\r\nassert(isequal(isparallel(p1,p2),y_correct))\r\n","published":true,"deleted":false,"likes_count":2,"comments_count":0,"created_by":20079,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":152,"test_suite_updated_at":"2013-12-20T15:17:23.000Z","rescore_all_solutions":false,"group_id":26,"created_at":"2013-12-20T14:46:59.000Z","updated_at":"2026-04-01T15:38:18.000Z","published_at":"2013-12-20T15:17:23.000Z","restored_at":null,"restored_by":null,"spam":false,"simulink":false,"admin_reviewed":false,"description_opc":"{\"relationships\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/document\",\"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\u003eReturn true or false depending on whether 2 vectors are parallel or not. Vectors can be 2 or 3 dimensional. The origin is not considered to be a vector in this problem. Vectors are row vectors.\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\u003eSo: p1=[0 0 0] p2=[1 2 3] output = false\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\u003ep1=[1 1]; p2=[4 4] output =true\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\\\" 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