// Numbas version: exam_results_page_options
{"name": "Draw a 3d plot with vis.js", "extensions": ["visjs", "stats"], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"variables": {"data": {"description": "<p>Some interesting-looking data: sum a few 2D normal distributions with different centres.</p>", "group": "Ungrouped variables", "definition": "gatherpoints(listsum(map(sample_peak(c[0],c[1],c[2],c[3]),c,centres)))", "templateType": "anything", "name": "data"}, "centres": {"description": "", "group": "Ungrouped variables", "definition": "repeat(let(d,random(2..4),[random(-5..5),d,random(-5..5),d]),3)", "templateType": "anything", "name": "centres"}}, "showQuestionGroupNames": false, "functions": {"listsum": {"parameters": [["lists", "list"]], "language": "jme", "definition": "if(len(lists)>0,lists[0]+listsum(lists[1..len(lists)]),[])", "type": "number"}, "sample_peak": {"parameters": [["x_mean", "number"], ["x_sd", "number"], ["y_mean", "number"], ["y_sd", "number"]], "language": "jme", "definition": "// generate a load of samples from a 2D normal distribution\nrepeat(\n    [round(normalsample(x_mean,x_sd)),round(normalsample(y_mean,y_sd))],\n    10000\n  )", "type": "number"}, "gatherpoints": {"parameters": [["data", "list"]], "language": "javascript", "definition": "// count the number of points at each coordinate\n// takes a list of [x,y] coordinates representing points\n// returns a list of data of the form [x,y,count]\n\ndata = data.sort(function(a,b){return a[0]<b[0] ? -1 : a[0]>b[0] ? 1 : a[1]<b[1] ? -1 : a[1]>b[1] ? 1 : 0});\nvar out = [];\nfor(var i=0;i<data.length;i++) {\n  var x = data[i][0];\n  var y = data[i][1];\n  var t = 0;\n  while(i<data.length && data[i][0]==x && data[i][1]==y) {\n    t += 1;\n    i += 1;\n  }\n  out.push([x,y,t]);\n}\nreturn out;", "type": "list"}}, "advice": "", "variablesTest": {"condition": "", "maxRuns": 100}, "type": "question", "statement": "<h4>A plot of a function</h4>\n<p>\\[ \\simplify{sin(x/50)*cos(x/50)*50+50} \\]</p>\n<p>{plot3dfunction(sin(x/50) * cos(y/50) * 50 + 50,x,0..300#6,y,0..300#6)}</p>\n<h4>Some random data</h4>\n<p>{plot3dpoints(data)}</p>\n<h4>Boxes instead of a surface</h4>\n<div id=\"boxes\">Boxes go here</div>", "ungrouped_variables": ["data", "centres"], "tags": [], "parts": [], "rulesets": {}, "preamble": {"js": "question.onHTMLAttached(function() {\n  var expr = Numbas.jme.compile('x*x-y*y');\n  var xvals = (new Numbas.jme.types.range([-5,5,1])).value.slice(3);\n  var yvals = (new Numbas.jme.types.range([-5,5,1])).value.slice(3);\n  var options = {\n    verticalRatio: 0.5,\n    style: 'bar-size'\n  }\n  var graph = Numbas.extensions.visjs.plot3dfunction(expr,question.scope,'x',xvals,'y',yvals,options);\n  $(question.display.html).find('#boxes').html(graph.containerElement);\n})", "css": ""}, "name": "Draw a 3d plot with vis.js", "variable_groups": [], "question_groups": [{"pickingStrategy": "all-ordered", "pickQuestions": 0, "questions": [], "name": ""}], "metadata": {"licence": "Creative Commons Attribution 4.0 International", "description": "<p>This question uses the vis.js library to&nbsp;plot 3D functions and data sets.</p>\n<p>As well as JME functions to make plots, you can use javascript functions to get more control over how the&nbsp;plots are rendered.</p>", "notes": ""}, "contributors": [{"name": "Christian Lawson-Perfect", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/7/"}]}]}], "contributors": [{"name": "Christian Lawson-Perfect", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/7/"}]}