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The change in ${tex`T`} at each time step is given by,`","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":633,"value":"tex.block`\\Delta T = \\Delta t\\: \\alpha\\Bigl(\\frac{T_{i+1,j}-2T_{i,j}+T_{i-1,j}}{\\Delta x^2} + \\frac{T_{i,j+1}-2T_{i,j}+T_{i,j-1}}{\\Delta y^2}\\Bigr)\\quad ,`","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":640,"value":"md `where is ${tex`\\Delta T`} is the change in ${tex`T`} and ${tex`\\Delta t`} is the size of the step in time. We store values of ${tex`T`} at many points along the plate, each with an ${tex`i,j`} index pair, where ${tex`i`} is the index in the ${tex`x`} direction and ${tex`j`} is the index in the ${tex`y`} direction.`","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":3,"value":"mutable T=TStart;","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":538,"value":"TStart = { // This is the initial temperature in the plate\n let T = new Array(nx);\n if (initial==\"Hot spot\") {\n for (let i=0; i 20 && i < 30 && j > 20 && j < 30) {\n Tj[j]=1.0;\n } else {\n Tj[j]=0.0;\n } \n }\n T[i]=Tj;\n }\n }\n if (initial==\"Hot spot and high T at y=0\") {for (let i=0; i 20 && i < 30 && j > 20 && j < 30) {\n Tj[j]=1.0;\n } else {\n Tj[j]=0.0;\n } \n }\n Tj[0]=1.0\n T[i]=Tj;\n }\n }\n if (initial==\"High T at x=0\") {for (let i=0; i d3.interpolateViridis)","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":28,"value":"//thresholds=d3.range(d3.min(Tdata),d3.max(Tdata),(d3.max(Tdata)-d3.min(Tdata))/21)\nthresholds = d3.range(-0.1,1.1,1.2/21);","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":502,"value":"nx=50","pinned":true,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":504,"value":"ny=50","pinned":true,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":506,"value":"dx=(xDomain[1]-xDomain[0])/nx","pinned":true,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":509,"value":"dy=(yDomain[1]-yDomain[0])/ny","pinned":true,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":152,"value":"// Converts from grid coordinates (indexes) to screen coordinates (pixels).\ntransform = ({type, value, coordinates}) => {\n return {type, value, coordinates: coordinates.map(rings => {\n return rings.map(points => {\n return points.map(([px, py]) => {\n px = px - 0.5;\n py = py - 0.5;\n px < 0 ? 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