{"group":{"id":1,"name":"Community","lockable":false,"created_at":"2012-01-18T18:02:15.000Z","updated_at":"2026-04-06T14:01:22.000Z","description":"Problems submitted by members of the MATLAB Central community.","is_default":true,"created_by":161519,"badge_id":null,"featured":false,"trending":false,"solution_count_in_trending_period":0,"trending_last_calculated":"2026-04-06T00:00:00.000Z","image_id":null,"published":true,"community_created":false,"status_id":2,"is_default_group_for_player":false,"deleted_by":null,"deleted_at":null,"restored_by":null,"restored_at":null,"description_opc":null,"description_html":null,"published_at":null},"problems":[{"id":48070,"title":"Center of Mass(es) in 3D Space","description":"Given a matrix of format [x1,y1,z1,m1; x2,y2,z2,m2 . . .], return the center of mass of all listed points in 3d space [xc,yc,zc]. Return pt_com = 'Bad Data' if any value for mass is negative\r\nInspired by: http://hyperphysics.phy-astr.gsu.edu/hbase/cm.html","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: 72px; display: block; min-width: 0px; padding-block-start: 0px; padding-top: 0px; perspective-origin: 407px 36px; transform-origin: 407px 36px; vertical-align: baseline; \"\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: 383.5px 8px; transform-origin: 383.5px 8px; unicode-bidi: normal; \"\u003e\u003cspan style=\"\"\u003eGiven a matrix of format [x1,y1,z1,m1; x2,y2,z2,m2 . . .], return the center of mass of all listed points in 3d space [xc,yc,zc]. Return pt_com = 'Bad Data' if any value for mass is negative\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: 38.5px 8px; transform-origin: 38.5px 8px; unicode-bidi: normal; \"\u003e\u003cspan style=\"\"\u003eInspired by: \u003c/span\u003e\u003c/span\u003e\u003ca target='_blank' href = \"/#null\"\u003e\u003cspan style=\"\"\u003e\u003cspan style=\"\"\u003ehttp://hyperphysics.phy-astr.gsu.edu/hbase/cm.html\u003c/span\u003e\u003c/span\u003e\u003c/a\u003e\u003c/div\u003e\u003c/div\u003e\u003c/div\u003e","function_template":"function pt_com = com_finder(x)\r\n pt_com = x;\r\nend","test_suite":"%%\r\nx = [10 4 12 65\r\n 3 5 8 6\r\n 7 2 13 11\r\n 10 1 6 32\r\n 8 5 2 77\r\n 4 6 9 6\r\n 4 6 15 8\r\n 7 1 6 38\r\n 6 3 8 44\r\n 2 1 1 68];\r\ny_correct = [6.7690,2.9606,6.0254];\r\nTOL = 1e-3;\r\nassert(all(abs(y_correct-com_finder(x))\u003c=TOL))\r\n\r\n%%\r\nx = [10 4 12 65\r\n 3 5 8 6\r\n 7 2 13 11\r\n 10 1 6 32\r\n 8 5 2 77\r\n 4 6 9 -6\r\n 4 6 15 8\r\n 7 1 6 38\r\n 6 3 8 44\r\n 2 1 1 68];\r\ny_correct = [6.7690,2.9606,6.0254];\r\nTOL = 1e-3;\r\nassert(isequal(com_finder(x),'Bad Data'))\r\n\r\n%%\r\n\r\nx = [-47 -41 -3 47\r\n -3 -121 -4 75\r\n -34 -68 -4 402\r\n -12 -137 -3 555\r\n -1 -106 -4 256\r\n -29 -157 -1 163\r\n -83 -106 -6 646\r\n -9 -55 -2 212\r\n -56 -149 -2 434\r\n -65 -157 -3 431\r\n -69 -162 -1 693\r\n -42 -153 -6 607\r\n -57 -16 -4 520\r\n -25 -42 -3 160\r\n -100 -151 -1 413\r\n -21 -51 -3 415\r\n -99 -29 -4 290\r\n -45 -63 -1 534\r\n -20 -135 -2 550\r\n -29 -134 -3 19\r\n -4 -178 -6 179\r\n -6 -72 -3 111\r\n -64 -60 -3 24\r\n -79 -100 -2 401\r\n -45 -200 -6 391\r\n -98 -129 -5 111\r\n -52 -64 -5 424\r\n -50 -47 -2 324\r\n -87 -176 -6 205\r\n -52 -49 -6 487\r\n -51 -200 -6 656\r\n -61 -69 -5 544\r\n -13 -153 -5 114\r\n -21 -2 -1 661\r\n -81 -159 -4 519\r\n -33 -9 -5 699\r\n -23 -42 -4 28\r\n -7 -34 -3 332\r\n -93 -140 -1 157\r\n -30 -80 -1 191\r\n -15 -124 -6 605\r\n -72 -118 -1 94\r\n -5 -127 -6 385\r\n -43 -190 -6 533\r\n -33 -191 -1 104\r\n -19 -56 -2 548\r\n -58 -18 -4 354\r\n -65 -182 -3 228\r\n -93 -131 -4 644\r\n -11 -184 -5 107\r\n -46 -54 -1 459\r\n -5 -100 -4 249\r\n -44 -28 -4 278\r\n -81 -18 -1 458\r\n -51 -39 -1 318\r\n -97 -26 -6 59\r\n -4 -134 -5 159\r\n -4 -167 -2 625\r\n -9 -144 -2 279\r\n -52 -138 -1 75\r\n -2 -156 -6 183\r\n -48 -173 -5 215\r\n -100 -15 -5 504\r\n -92 -21 -4 467\r\n -9 -144 -5 690\r\n -81 -99 -4 529\r\n -26 -104 -1 101\r\n -9 -175 -1 472\r\n -68 -79 -5 77\r\n -96 -196 -3 418\r\n -83 -162 -3 60\r\n -64 -54 -6 323\r\n -78 -31 -2 174\r\n -26 -55 -2 243\r\n -41 -24 -6 47\r\n -90 -178 -2 448\r\n -97 -136 -1 33\r\n -18 -43 -5 213\r\n -20 -103 -4 141\r\n -46 -106 -1 59\r\n -44 -74 -5 266\r\n -74 -141 -5 109\r\n -48 -92 -6 199\r\n -40 -90 -1 76\r\n -9 -93 -5 486\r\n -68 -43 -2 313\r\n -21 -57 -2 400\r\n -32 -81 -5 3\r\n -46 -108 -6 149\r\n -72 -26 -4 336\r\n -26 -47 -4 35\r\n -37 -66 -1 576\r\n -51 -75 -1 97\r\n -91 -18 -5 655\r\n -16 -49 -6 686\r\n -49 -12 -4 436\r\n -17 -199 -6 181\r\n -56 -11 -6 665\r\n -51 -44 -2 14\r\n -34 -34 -6 317\r\n -81 -18 -2 82\r\n -27 -111 -2 24\r\n -14 -70 -3 184\r\n -14 -66 -4 329\r\n -3 -74 -5 199\r\n -97 -24 -1 523\r\n -3 -27 -1 47\r\n -90 -95 -4 119\r\n -31 -4 -3 164\r\n -43 -42 -6 402\r\n -3 -46 -1 249\r\n -62 -140 -4 459\r\n -40 -13 -3 38\r\n -70 -170 -6 470\r\n -17 -19 -5 148\r\n -4 -156 -6 542\r\n -57 -92 -4 432\r\n -64 -160 -3 429\r\n -8 -129 -6 279\r\n -99 -52 -6 115\r\n -85 -82 -2 106\r\n -85 -86 -5 257\r\n -53 -147 -5 396\r\n -49 -161 -3 190\r\n -8 -43 -5 460\r\n -4 -128 -2 40\r\n -23 -51 -6 245\r\n -78 -198 -1 421\r\n -99 -33 -3 96\r\n -64 -117 -6 259\r\n -96 -26 -5 695\r\n -53 -17 -6 561\r\n -76 -43 -2 266\r\n -56 -3 -2 438\r\n -93 -54 -6 222\r\n -78 -34 -1 389\r\n -47 -124 -5 178\r\n -64 -41 -1 98\r\n -90 -196 -4 631\r\n -33 -35 -6 278\r\n -33 -31 -2 283\r\n -36 -11 -6 464\r\n -58 -139 -4 564\r\n -75 -43 -3 372\r\n -28 -51 -2 626\r\n -59 -133 -5 115\r\n -1 -12 -4 74\r\n -5 -10 -3 401\r\n -58 -6 -4 455\r\n -20 -125 -1 690\r\n -12 -126 -1 62\r\n -16 -54 -4 443\r\n -55 -193 -4 587\r\n -20 -54 -1 433\r\n -85 -42 -4 324\r\n -1 -198 -3 436\r\n -77 -184 -2 279\r\n -89 -195 -1 82\r\n -61 -118 -4 274\r\n -31 -36 -4 483\r\n -9 -104 -6 80\r\n -91 -26 -4 603\r\n -73 -31 -2 124\r\n -62 -15 -4 128\r\n -10 -69 -5 597\r\n -53 -78 -4 640\r\n -99 -118 -3 26\r\n -57 -118 -5 79\r\n -14 -151 -5 332\r\n -46 -137 -3 246\r\n -33 -49 -1 429\r\n -3 -139 -4 639\r\n -92 -200 -3 85\r\n -17 -83 -2 350\r\n -14 -95 -6 690\r\n -36 -157 -3 621\r\n -40 -165 -2 491\r\n -86 -12 -5 104\r\n -99 -176 -4 686\r\n -26 -17 -6 477\r\n -52 -62 -6 241\r\n -7 -9 -2 519\r\n -13 -106 -6 551\r\n -75 -83 -4 31\r\n -29 -17 -2 209\r\n -92 -175 -4 221\r\n -30 -83 -2 581\r\n -14 -28 -4 356\r\n -67 -85 -6 301\r\n -73 -89 -5 8\r\n -13 -5 -2 81\r\n -40 -80 -4 632\r\n -97 -50 -3 284\r\n -57 -73 -1 322\r\n -99 -17 -1 587\r\n -51 -67 -6 450\r\n -77 -107 -1 201\r\n -94 -48 -4 303\r\n -85 -96 -1 101\r\n -22 -30 -4 118\r\n -7 -87 -1 512\r\n -38 -132 -3 136\r\n -77 -179 -2 298\r\n -70 -122 -6 435\r\n -84 -107 -1 364\r\n -54 -62 -6 260\r\n -9 -106 -4 567\r\n -18 -104 -2 165\r\n -12 -86 -5 523\r\n -51 -25 -6 374\r\n -45 -47 -6 139\r\n -68 -85 -4 658\r\n -39 -40 -1 407\r\n -86 -148 -4 176\r\n -45 -99 -4 500\r\n -72 -93 -1 252\r\n -13 -98 -2 361\r\n -48 -24 -4 559\r\n -90 -72 -2 605\r\n -89 -6 -5 440\r\n -94 -66 -2 237\r\n -37 -166 -6 422\r\n -91 -9 -4 217\r\n -88 -120 -2 57\r\n -29 -116 -1 457\r\n -7 -115 -2 591\r\n -23 -195 -3 232\r\n -34 -102 -3 131\r\n -84 -123 -4 572\r\n -25 -72 -2 587\r\n -53 -186 -6 252\r\n -21 -73 -3 631\r\n -34 -80 -1 654\r\n -82 -6 -1 329\r\n -86 -173 -5 48\r\n -6 -163 -5 567\r\n -67 -31 -5 688\r\n -74 -54 -1 117\r\n -44 -167 -2 27\r\n -66 -86 -4 143\r\n -20 -122 -6 373\r\n -69 -163 -3 537\r\n -88 -13 -3 254\r\n -66 -87 -5 310\r\n -19 -28 -4 127\r\n -32 -158 -3 318\r\n -9 -189 -4 335\r\n -41 -79 -3 30\r\n -56 -196 -5 630\r\n -46 -39 -6 153\r\n -58 -104 -1 43\r\n -40 -94 -3 37\r\n -88 -156 -1 137\r\n -43 -45 -1 197\r\n -49 -31 -3 281\r\n -31 -154 -2 191\r\n -86 -64 -1 271\r\n -95 -159 -3 598\r\n -74 -47 -3 335\r\n -61 -104 -4 368\r\n -49 -169 -4 553\r\n -37 -90 -3 294\r\n -26 -164 -1 624\r\n -9 -17 -2 327\r\n -81 -188 -6 226\r\n -60 -90 -6 129\r\n -10 -150 -3 396\r\n -42 -109 -3 131\r\n -73 -161 -4 308\r\n -53 -9 -6 2\r\n -96 -106 -6 459\r\n -78 -17 -1 253\r\n -61 -187 -5 524\r\n -61 -54 -5 120\r\n -84 -58 -2 317\r\n -42 -71 -1 675\r\n -44 -80 -5 560\r\n -24 -131 -6 308\r\n -30 -62 -3 648\r\n -67 -47 -6 529\r\n -39 -120 -5 453\r\n -34 -104 -1 203\r\n -3 -109 -3 327\r\n -79 -28 -1 222\r\n -43 -169 -6 15\r\n -32 -66 -4 529\r\n -87 -22 -1 584\r\n -44 -76 -5 308\r\n -53 -126 -5 48\r\n -62 -80 -5 648\r\n -44 -68 -5 104\r\n -33 -38 -6 188\r\n -46 -25 -6 29\r\n -23 -148 -3 103\r\n -98 -200 -4 106\r\n -39 -94 -6 397\r\n -77 -72 -2 125\r\n -1 -64 -2 560\r\n -89 -161 -3 673\r\n -91 -198 -3 526];\r\ny_correct = [-48.2024,-92.6248,-3.6100];\r\nTOL = 1e-3;\r\nassert(all(abs(y_correct-com_finder(x))\u003c=TOL))\r\n\r\n%%\r\nx = [(0:5:500)',(0:6:600)',(0:7:700)',(0:1:100)'];\r\ny_correct = [335.0000,402.0000,469.0000];\r\nTOL = 1e-3;\r\nassert(all(abs(y_correct-com_finder(x))\u003c=TOL))\r\n\r\n%%\r\nx = [(0:-5:-500)',(0:6:600)',(0:-7:-700)',(0:8:800)'];\r\ny_correct = [-335.0000,402.0000,-469.0000];\r\nTOL = 1e-3;\r\nassert(all(abs(y_correct-com_finder(x))\u003c=TOL))\r\n\r\n%%\r\nx = circshift(spiral(4),2,2)-2;\r\nassert(isequal(com_finder(x),'Bad Data'))\r\n\r\n%%\r\nid = randi([7 11]);\r\nx = randi(100,id,4);\r\nx(id,4) = -x(id,4);\r\nassert(isequal(com_finder(x),'Bad Data'))\r\n\r\n%%\r\nx = [zeros(17,3) (1:17)'];\r\ny_correct = zeros(1,3);\r\nTOL = 1e-3;\r\nassert(all(abs(y_correct-com_finder(x))\u003c=TOL))\r\n\r\n\r\n%%\r\n%Cheating is bad\r\nfunctions={'!','feval','eval','str2func','str2num','regex','system','dos','unix','perl','assert','fopen','write','save','setenv','path','please'};\r\nassessFunctionAbsence(functions, 'FileName', 'com_finder.m');\r\n","published":true,"deleted":false,"likes_count":1,"comments_count":0,"created_by":728283,"edited_by":223089,"edited_at":"2023-02-02T12:44:18.000Z","deleted_by":null,"deleted_at":null,"solvers_count":17,"test_suite_updated_at":"2023-02-02T12:44:18.000Z","rescore_all_solutions":false,"group_id":1,"created_at":"2020-12-17T20:58:08.000Z","updated_at":"2026-03-05T14:22:01.000Z","published_at":"2020-12-18T16:06:36.000Z","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\u003eGiven a matrix of format [x1,y1,z1,m1; x2,y2,z2,m2 . . .], return the center of mass of all listed points in 3d space [xc,yc,zc]. Return pt_com = 'Bad Data' if any value for mass is negative\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\u003eInspired by: \u003c/w:t\u003e\u003c/w:r\u003e\u003cw:hyperlink w:docLocation=\\\"\\\"\u003e\u003cw:r\u003e\u003cw:t\u003ehttp://hyperphysics.phy-astr.gsu.edu/hbase/cm.html\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\"}]}"}],"problem_search":{"errors":[],"problems":[{"id":48070,"title":"Center of Mass(es) in 3D Space","description":"Given a matrix of format [x1,y1,z1,m1; x2,y2,z2,m2 . . .], return the center of mass of all listed points in 3d space [xc,yc,zc]. Return pt_com = 'Bad Data' if any value for mass is negative\r\nInspired by: http://hyperphysics.phy-astr.gsu.edu/hbase/cm.html","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: 72px; display: block; min-width: 0px; padding-block-start: 0px; padding-top: 0px; perspective-origin: 407px 36px; transform-origin: 407px 36px; vertical-align: baseline; \"\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: 383.5px 8px; transform-origin: 383.5px 8px; unicode-bidi: normal; \"\u003e\u003cspan style=\"\"\u003eGiven a matrix of format [x1,y1,z1,m1; x2,y2,z2,m2 . . .], return the center of mass of all listed points in 3d space [xc,yc,zc]. Return pt_com = 'Bad Data' if any value for mass is negative\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: 38.5px 8px; transform-origin: 38.5px 8px; unicode-bidi: normal; \"\u003e\u003cspan style=\"\"\u003eInspired by: \u003c/span\u003e\u003c/span\u003e\u003ca target='_blank' href = \"/#null\"\u003e\u003cspan style=\"\"\u003e\u003cspan style=\"\"\u003ehttp://hyperphysics.phy-astr.gsu.edu/hbase/cm.html\u003c/span\u003e\u003c/span\u003e\u003c/a\u003e\u003c/div\u003e\u003c/div\u003e\u003c/div\u003e","function_template":"function pt_com = com_finder(x)\r\n pt_com = x;\r\nend","test_suite":"%%\r\nx = [10 4 12 65\r\n 3 5 8 6\r\n 7 2 13 11\r\n 10 1 6 32\r\n 8 5 2 77\r\n 4 6 9 6\r\n 4 6 15 8\r\n 7 1 6 38\r\n 6 3 8 44\r\n 2 1 1 68];\r\ny_correct = [6.7690,2.9606,6.0254];\r\nTOL = 1e-3;\r\nassert(all(abs(y_correct-com_finder(x))\u003c=TOL))\r\n\r\n%%\r\nx = [10 4 12 65\r\n 3 5 8 6\r\n 7 2 13 11\r\n 10 1 6 32\r\n 8 5 2 77\r\n 4 6 9 -6\r\n 4 6 15 8\r\n 7 1 6 38\r\n 6 3 8 44\r\n 2 1 1 68];\r\ny_correct = [6.7690,2.9606,6.0254];\r\nTOL = 1e-3;\r\nassert(isequal(com_finder(x),'Bad Data'))\r\n\r\n%%\r\n\r\nx = [-47 -41 -3 47\r\n -3 -121 -4 75\r\n -34 -68 -4 402\r\n -12 -137 -3 555\r\n -1 -106 -4 256\r\n -29 -157 -1 163\r\n -83 -106 -6 646\r\n -9 -55 -2 212\r\n -56 -149 -2 434\r\n -65 -157 -3 431\r\n -69 -162 -1 693\r\n -42 -153 -6 607\r\n -57 -16 -4 520\r\n -25 -42 -3 160\r\n -100 -151 -1 413\r\n -21 -51 -3 415\r\n -99 -29 -4 290\r\n -45 -63 -1 534\r\n -20 -135 -2 550\r\n -29 -134 -3 19\r\n -4 -178 -6 179\r\n -6 -72 -3 111\r\n -64 -60 -3 24\r\n -79 -100 -2 401\r\n -45 -200 -6 391\r\n -98 -129 -5 111\r\n -52 -64 -5 424\r\n -50 -47 -2 324\r\n -87 -176 -6 205\r\n -52 -49 -6 487\r\n -51 -200 -6 656\r\n -61 -69 -5 544\r\n -13 -153 -5 114\r\n -21 -2 -1 661\r\n -81 -159 -4 519\r\n -33 -9 -5 699\r\n -23 -42 -4 28\r\n -7 -34 -3 332\r\n -93 -140 -1 157\r\n -30 -80 -1 191\r\n -15 -124 -6 605\r\n -72 -118 -1 94\r\n -5 -127 -6 385\r\n -43 -190 -6 533\r\n -33 -191 -1 104\r\n -19 -56 -2 548\r\n -58 -18 -4 354\r\n -65 -182 -3 228\r\n -93 -131 -4 644\r\n -11 -184 -5 107\r\n -46 -54 -1 459\r\n -5 -100 -4 249\r\n -44 -28 -4 278\r\n -81 -18 -1 458\r\n -51 -39 -1 318\r\n -97 -26 -6 59\r\n -4 -134 -5 159\r\n -4 -167 -2 625\r\n -9 -144 -2 279\r\n -52 -138 -1 75\r\n -2 -156 -6 183\r\n -48 -173 -5 215\r\n -100 -15 -5 504\r\n -92 -21 -4 467\r\n -9 -144 -5 690\r\n -81 -99 -4 529\r\n -26 -104 -1 101\r\n -9 -175 -1 472\r\n -68 -79 -5 77\r\n -96 -196 -3 418\r\n -83 -162 -3 60\r\n -64 -54 -6 323\r\n -78 -31 -2 174\r\n -26 -55 -2 243\r\n -41 -24 -6 47\r\n -90 -178 -2 448\r\n -97 -136 -1 33\r\n -18 -43 -5 213\r\n -20 -103 -4 141\r\n -46 -106 -1 59\r\n -44 -74 -5 266\r\n -74 -141 -5 109\r\n -48 -92 -6 199\r\n -40 -90 -1 76\r\n -9 -93 -5 486\r\n -68 -43 -2 313\r\n -21 -57 -2 400\r\n -32 -81 -5 3\r\n -46 -108 -6 149\r\n -72 -26 -4 336\r\n -26 -47 -4 35\r\n -37 -66 -1 576\r\n -51 -75 -1 97\r\n -91 -18 -5 655\r\n -16 -49 -6 686\r\n -49 -12 -4 436\r\n -17 -199 -6 181\r\n -56 -11 -6 665\r\n -51 -44 -2 14\r\n -34 -34 -6 317\r\n -81 -18 -2 82\r\n -27 -111 -2 24\r\n -14 -70 -3 184\r\n -14 -66 -4 329\r\n -3 -74 -5 199\r\n -97 -24 -1 523\r\n -3 -27 -1 47\r\n -90 -95 -4 119\r\n -31 -4 -3 164\r\n -43 -42 -6 402\r\n -3 -46 -1 249\r\n -62 -140 -4 459\r\n -40 -13 -3 38\r\n -70 -170 -6 470\r\n -17 -19 -5 148\r\n -4 -156 -6 542\r\n -57 -92 -4 432\r\n -64 -160 -3 429\r\n -8 -129 -6 279\r\n -99 -52 -6 115\r\n -85 -82 -2 106\r\n -85 -86 -5 257\r\n -53 -147 -5 396\r\n -49 -161 -3 190\r\n -8 -43 -5 460\r\n -4 -128 -2 40\r\n -23 -51 -6 245\r\n -78 -198 -1 421\r\n -99 -33 -3 96\r\n -64 -117 -6 259\r\n -96 -26 -5 695\r\n -53 -17 -6 561\r\n -76 -43 -2 266\r\n -56 -3 -2 438\r\n -93 -54 -6 222\r\n -78 -34 -1 389\r\n -47 -124 -5 178\r\n -64 -41 -1 98\r\n -90 -196 -4 631\r\n -33 -35 -6 278\r\n -33 -31 -2 283\r\n -36 -11 -6 464\r\n -58 -139 -4 564\r\n -75 -43 -3 372\r\n -28 -51 -2 626\r\n -59 -133 -5 115\r\n -1 -12 -4 74\r\n -5 -10 -3 401\r\n -58 -6 -4 455\r\n -20 -125 -1 690\r\n -12 -126 -1 62\r\n -16 -54 -4 443\r\n -55 -193 -4 587\r\n -20 -54 -1 433\r\n -85 -42 -4 324\r\n -1 -198 -3 436\r\n -77 -184 -2 279\r\n -89 -195 -1 82\r\n -61 -118 -4 274\r\n -31 -36 -4 483\r\n -9 -104 -6 80\r\n -91 -26 -4 603\r\n -73 -31 -2 124\r\n -62 -15 -4 128\r\n -10 -69 -5 597\r\n -53 -78 -4 640\r\n -99 -118 -3 26\r\n -57 -118 -5 79\r\n -14 -151 -5 332\r\n -46 -137 -3 246\r\n -33 -49 -1 429\r\n -3 -139 -4 639\r\n -92 -200 -3 85\r\n -17 -83 -2 350\r\n -14 -95 -6 690\r\n -36 -157 -3 621\r\n -40 -165 -2 491\r\n -86 -12 -5 104\r\n -99 -176 -4 686\r\n -26 -17 -6 477\r\n -52 -62 -6 241\r\n -7 -9 -2 519\r\n -13 -106 -6 551\r\n -75 -83 -4 31\r\n -29 -17 -2 209\r\n -92 -175 -4 221\r\n -30 -83 -2 581\r\n -14 -28 -4 356\r\n -67 -85 -6 301\r\n -73 -89 -5 8\r\n -13 -5 -2 81\r\n -40 -80 -4 632\r\n -97 -50 -3 284\r\n -57 -73 -1 322\r\n -99 -17 -1 587\r\n -51 -67 -6 450\r\n -77 -107 -1 201\r\n -94 -48 -4 303\r\n -85 -96 -1 101\r\n -22 -30 -4 118\r\n -7 -87 -1 512\r\n -38 -132 -3 136\r\n -77 -179 -2 298\r\n -70 -122 -6 435\r\n -84 -107 -1 364\r\n -54 -62 -6 260\r\n -9 -106 -4 567\r\n -18 -104 -2 165\r\n -12 -86 -5 523\r\n -51 -25 -6 374\r\n -45 -47 -6 139\r\n -68 -85 -4 658\r\n -39 -40 -1 407\r\n -86 -148 -4 176\r\n -45 -99 -4 500\r\n -72 -93 -1 252\r\n -13 -98 -2 361\r\n -48 -24 -4 559\r\n -90 -72 -2 605\r\n -89 -6 -5 440\r\n -94 -66 -2 237\r\n -37 -166 -6 422\r\n -91 -9 -4 217\r\n -88 -120 -2 57\r\n -29 -116 -1 457\r\n -7 -115 -2 591\r\n -23 -195 -3 232\r\n -34 -102 -3 131\r\n -84 -123 -4 572\r\n -25 -72 -2 587\r\n -53 -186 -6 252\r\n -21 -73 -3 631\r\n -34 -80 -1 654\r\n -82 -6 -1 329\r\n -86 -173 -5 48\r\n -6 -163 -5 567\r\n -67 -31 -5 688\r\n -74 -54 -1 117\r\n -44 -167 -2 27\r\n -66 -86 -4 143\r\n -20 -122 -6 373\r\n -69 -163 -3 537\r\n -88 -13 -3 254\r\n -66 -87 -5 310\r\n -19 -28 -4 127\r\n -32 -158 -3 318\r\n -9 -189 -4 335\r\n -41 -79 -3 30\r\n -56 -196 -5 630\r\n -46 -39 -6 153\r\n -58 -104 -1 43\r\n -40 -94 -3 37\r\n -88 -156 -1 137\r\n -43 -45 -1 197\r\n -49 -31 -3 281\r\n -31 -154 -2 191\r\n -86 -64 -1 271\r\n -95 -159 -3 598\r\n -74 -47 -3 335\r\n -61 -104 -4 368\r\n -49 -169 -4 553\r\n -37 -90 -3 294\r\n -26 -164 -1 624\r\n -9 -17 -2 327\r\n -81 -188 -6 226\r\n -60 -90 -6 129\r\n -10 -150 -3 396\r\n -42 -109 -3 131\r\n -73 -161 -4 308\r\n -53 -9 -6 2\r\n -96 -106 -6 459\r\n -78 -17 -1 253\r\n -61 -187 -5 524\r\n -61 -54 -5 120\r\n -84 -58 -2 317\r\n -42 -71 -1 675\r\n -44 -80 -5 560\r\n -24 -131 -6 308\r\n -30 -62 -3 648\r\n -67 -47 -6 529\r\n -39 -120 -5 453\r\n -34 -104 -1 203\r\n -3 -109 -3 327\r\n -79 -28 -1 222\r\n -43 -169 -6 15\r\n -32 -66 -4 529\r\n -87 -22 -1 584\r\n -44 -76 -5 308\r\n -53 -126 -5 48\r\n -62 -80 -5 648\r\n -44 -68 -5 104\r\n -33 -38 -6 188\r\n -46 -25 -6 29\r\n -23 -148 -3 103\r\n -98 -200 -4 106\r\n -39 -94 -6 397\r\n -77 -72 -2 125\r\n -1 -64 -2 560\r\n -89 -161 -3 673\r\n -91 -198 -3 526];\r\ny_correct = [-48.2024,-92.6248,-3.6100];\r\nTOL = 1e-3;\r\nassert(all(abs(y_correct-com_finder(x))\u003c=TOL))\r\n\r\n%%\r\nx = [(0:5:500)',(0:6:600)',(0:7:700)',(0:1:100)'];\r\ny_correct = [335.0000,402.0000,469.0000];\r\nTOL = 1e-3;\r\nassert(all(abs(y_correct-com_finder(x))\u003c=TOL))\r\n\r\n%%\r\nx = [(0:-5:-500)',(0:6:600)',(0:-7:-700)',(0:8:800)'];\r\ny_correct = [-335.0000,402.0000,-469.0000];\r\nTOL = 1e-3;\r\nassert(all(abs(y_correct-com_finder(x))\u003c=TOL))\r\n\r\n%%\r\nx = circshift(spiral(4),2,2)-2;\r\nassert(isequal(com_finder(x),'Bad Data'))\r\n\r\n%%\r\nid = randi([7 11]);\r\nx = randi(100,id,4);\r\nx(id,4) = -x(id,4);\r\nassert(isequal(com_finder(x),'Bad Data'))\r\n\r\n%%\r\nx = [zeros(17,3) (1:17)'];\r\ny_correct = zeros(1,3);\r\nTOL = 1e-3;\r\nassert(all(abs(y_correct-com_finder(x))\u003c=TOL))\r\n\r\n\r\n%%\r\n%Cheating is bad\r\nfunctions={'!','feval','eval','str2func','str2num','regex','system','dos','unix','perl','assert','fopen','write','save','setenv','path','please'};\r\nassessFunctionAbsence(functions, 'FileName', 'com_finder.m');\r\n","published":true,"deleted":false,"likes_count":1,"comments_count":0,"created_by":728283,"edited_by":223089,"edited_at":"2023-02-02T12:44:18.000Z","deleted_by":null,"deleted_at":null,"solvers_count":17,"test_suite_updated_at":"2023-02-02T12:44:18.000Z","rescore_all_solutions":false,"group_id":1,"created_at":"2020-12-17T20:58:08.000Z","updated_at":"2026-03-05T14:22:01.000Z","published_at":"2020-12-18T16:06:36.000Z","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\u003eGiven a matrix of format [x1,y1,z1,m1; x2,y2,z2,m2 . . .], return the center of mass of all listed points in 3d space [xc,yc,zc]. Return pt_com = 'Bad Data' if any value for mass is negative\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\u003eInspired by: \u003c/w:t\u003e\u003c/w:r\u003e\u003cw:hyperlink w:docLocation=\\\"\\\"\u003e\u003cw:r\u003e\u003cw:t\u003ehttp://hyperphysics.phy-astr.gsu.edu/hbase/cm.html\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\"}]}"}],"term":"tag:\"com\"","current_player_id":null,"fields":[{"name":"page","type":"integer","callback":null,"default":1,"directive":null,"facet":null,"facet_method":"and","operator":null,"param":null,"static":null,"prepend":true},{"name":"per_page","type":"integer","callback":null,"default":50,"directive":null,"facet":null,"facet_method":"and","operator":null,"param":null,"static":null,"prepend":true},{"name":"sort","type":"string","callback":null,"default":null,"directive":null,"facet":null,"facet_method":"and","operator":null,"param":null,"static":null,"prepend":true},{"name":"body","type":"text","callback":null,"default":"*:*","directive":null,"facet":null,"facet_method":"and","operator":null,"param":"term","static":null,"prepend":false},{"name":"group","type":"string","callback":null,"default":null,"directive":"group","facet":true,"facet_method":"and","operator":null,"param":"term","static":null,"prepend":true},{"name":"difficulty_rating_bin","type":"string","callback":null,"default":null,"directive":"difficulty_rating_bin","facet":true,"facet_method":"and","operator":null,"param":"term","static":null,"prepend":true},{"name":"id","type":"integer","callback":null,"default":null,"directive":"id","facet":null,"facet_method":"and","operator":null,"param":"term","static":null,"prepend":true},{"name":"tag","type":"string","callback":null,"default":null,"directive":"tag","facet":null,"facet_method":"and","operator":null,"param":"term","static":null,"prepend":true},{"name":"product","type":"string","callback":null,"default":null,"directive":"product","facet":null,"facet_method":"and","operator":null,"param":"term","static":null,"prepend":true},{"name":"created_at","type":"timeframe","callback":{},"default":null,"directive":"created_at","facet":null,"facet_method":"and","operator":null,"param":"term","static":null,"prepend":true},{"name":"profile_id","type":"integer","callback":null,"default":null,"directive":"author_id","facet":null,"facet_method":"and","operator":null,"param":"term","static":null,"prepend":true},{"name":"created_by","type":"string","callback":null,"default":null,"directive":"author","facet":null,"facet_method":"and","operator":null,"param":"term","static":null,"prepend":true},{"name":"player_id","type":"integer","callback":null,"default":null,"directive":"solver_id","facet":null,"facet_method":"and","operator":null,"param":"term","static":null,"prepend":true},{"name":"player","type":"string","callback":null,"default":null,"directive":"solver","facet":null,"facet_method":"and","operator":null,"param":"term","static":null,"prepend":true},{"name":"solvers_count","type":"integer","callback":null,"default":null,"directive":"solvers_count","facet":null,"facet_method":"and","operator":null,"param":"term","static":null,"prepend":true},{"name":"comments_count","type":"integer","callback":null,"default":null,"directive":"comments_count","facet":null,"facet_method":"and","operator":null,"param":"term","static":null,"prepend":true},{"name":"likes_count","type":"integer","callback":null,"default":null,"directive":"likes_count","facet":null,"facet_method":"and","operator":null,"param":"term","static":null,"prepend":true},{"name":"leader_id","type":"integer","callback":null,"default":null,"directive":"leader_id","facet":null,"facet_method":"and","operator":null,"param":"term","static":null,"prepend":true},{"name":"leading_solution","type":"integer","callback":null,"default":null,"directive":"leading_solution","facet":null,"facet_method":"and","operator":null,"param":"term","static":null,"prepend":true}],"filters":[{"name":"asset_type","type":"string","callback":null,"default":null,"directive":null,"facet":null,"facet_method":"and","operator":null,"param":null,"static":"\"cody:problem\"","prepend":true},{"name":"profile_id","type":"integer","callback":{},"default":null,"directive":null,"facet":null,"facet_method":"and","operator":null,"param":"author_id","static":null,"prepend":true}],"query":{"params":{"per_page":50,"term":"tag:\"com\"","current_player":null,"sort":"map(difficulty_value,0,0,999) asc"},"parser":"MathWorks::Search::Solr::QueryParser","directives":{"term":{"directives":{"tag":[["tag:\"com\"","","\"","com","\""]]}}},"facets":{"#\u003cMathWorks::Search::Field:0x00007f03b9e0e250\u003e":null,"#\u003cMathWorks::Search::Field:0x00007f03b9e0e1b0\u003e":null},"filters":{"#\u003cMathWorks::Search::Field:0x00007f03b9e0d8f0\u003e":"\"cody:problem\""},"fields":{"#\u003cMathWorks::Search::Field:0x00007f03b9e0e4d0\u003e":1,"#\u003cMathWorks::Search::Field:0x00007f03b9e0e430\u003e":50,"#\u003cMathWorks::Search::Field:0x00007f03b9e0e390\u003e":"map(difficulty_value,0,0,999) asc","#\u003cMathWorks::Search::Field:0x00007f03b9e0e2f0\u003e":"tag:\"com\""},"user_query":{"#\u003cMathWorks::Search::Field:0x00007f03b9e0e2f0\u003e":"tag:\"com\""},"queried_facets":{}},"query_backend":{"connection":{"configuration":{"index_url":"http://index-op-v2/solr/","query_url":"http://search-op-v2/solr/","direct_access_index_urls":["http://index-op-v2/solr/"],"direct_access_query_urls":["http://search-op-v2/solr/"],"timeout":10,"vhost":"search","exchange":"search.topic","heartbeat":30,"pre_index_mode":false,"host":"rabbitmq-eks","port":5672,"username":"cody-search","password":"78X075ddcV44","virtual_host":"search","indexer":"amqp","http_logging":"true","core":"cody"},"query_connection":{"uri":"http://search-op-v2/solr/cody/","proxy":null,"connection":{"parallel_manager":null,"headers":{"User-Agent":"Faraday v1.0.1"},"params":{},"options":{"params_encoder":"Faraday::FlatParamsEncoder","proxy":null,"bind":null,"timeout":null,"open_timeout":null,"read_timeout":null,"write_timeout":null,"boundary":null,"oauth":null,"context":null,"on_data":null},"ssl":{"verify":true,"ca_file":null,"ca_path":null,"verify_mode":null,"cert_store":null,"client_cert":null,"client_key":null,"certificate":null,"private_key":null,"verify_depth":null,"version":null,"min_version":null,"max_version":null},"default_parallel_manager":null,"builder":{"adapter":{"name":"Faraday::Adapter::NetHttp","args":[],"block":null},"handlers":[{"name":"Faraday::Response::RaiseError","args":[],"block":null}],"app":{"app":{"ssl_cert_store":{"verify_callback":null,"error":null,"error_string":null,"chain":null,"time":null},"app":{},"connection_options":{},"config_block":null}}},"url_prefix":"http://search-op-v2/solr/cody/","manual_proxy":false,"proxy":null},"update_format":"RSolr::JSON::Generator","update_path":"update","options":{"url":"http://search-op-v2/solr/cody"}}},"query":{"params":{"per_page":50,"term":"tag:\"com\"","current_player":null,"sort":"map(difficulty_value,0,0,999) asc"},"parser":"MathWorks::Search::Solr::QueryParser","directives":{"term":{"directives":{"tag":[["tag:\"com\"","","\"","com","\""]]}}},"facets":{"#\u003cMathWorks::Search::Field:0x00007f03b9e0e250\u003e":null,"#\u003cMathWorks::Search::Field:0x00007f03b9e0e1b0\u003e":null},"filters":{"#\u003cMathWorks::Search::Field:0x00007f03b9e0d8f0\u003e":"\"cody:problem\""},"fields":{"#\u003cMathWorks::Search::Field:0x00007f03b9e0e4d0\u003e":1,"#\u003cMathWorks::Search::Field:0x00007f03b9e0e430\u003e":50,"#\u003cMathWorks::Search::Field:0x00007f03b9e0e390\u003e":"map(difficulty_value,0,0,999) asc","#\u003cMathWorks::Search::Field:0x00007f03b9e0e2f0\u003e":"tag:\"com\""},"user_query":{"#\u003cMathWorks::Search::Field:0x00007f03b9e0e2f0\u003e":"tag:\"com\""},"queried_facets":{}},"options":{"fields":["id","difficulty_rating"]},"join":" "},"results":[{"id":48070,"difficulty_rating":"easy"}]}}