I'm a professor of mathematics at the University of North Carolina Asheville. I've also done a fair amount of consulting work over the years focusing on scientific and data visualization.
I'm happy to be part of the first Observable Ambassador's cohort.
Public
Edited
Dec 18, 2022
Importers
2 stars
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PlotX3D
function string_add(s1, s2) {
let v2 = s2.split(' ');
return s1.split(' ')
.map((v, i) => parseFloat(v) + parseFloat(v2[i]))
.join(' ');
}
function chop(x) {
return Math.abs(x) < 0.000001 ? 0 : x;
}
function cross([x1, y1, z1], [x2, y2, z2]) {
return [
y1 * z2 - z1 * y2,
z1 * x2 - x1 * z2,
x1 * y2 - y1 * x2
];
}
function dot([x1, y1, z1], [x2, y2, z2]) {
return x1 * x2 + y1 * y2 + z1 * z2;
}
function diff([x1, y1, z1], [x2, y2, z2]) {
return [x2 - x1, y2 - y1, z2 - z1];
}
function sum([x1, y1, z1], [x2, y2, z2]) {
return [x2 + x1, y2 + y1, z2 + z1];
}
function negate([x, y, z]) {
return [-x, -y, -z];
}
function norm([v0, v1, v2]) {
return Math.sqrt(v0 * v0 + v1 * v1 + v2 * v2);
}
function normalize(v) {
let [x, y, z] = v;
let n = norm(v);
return [x / n, y / n, z / n];
}
function scale(r, [x, y, z]) {
return [r * x, r * y, r * z];
}
function pt_toString([x, y, z]) {
return ` ${x} ${y} ${z}`;
}
function path_list_to_indexString(paths) {
let cnt = 0;
let individual_indices = paths.map(function(l) {
let result = d3.range(l.length).map(x => x + cnt);
cnt = cnt + l.length;
return result.toString();
});
return individual_indices
.map(s => s + ' -1')
.toString()
.replace(/,/g, ' ');
}
function pt_list_to_colorString(pt_list,f) {
return pt_list.map(pt_toString).toString();
}
function pt_list_to_coordString(pt_list) {
return pt_list.map(pt_toString).toString();
}
function path_list_to_coordString(paths) {
return paths.map(pt_list_to_coordString).toString();
}
// Rotate u1 so that it points in direction v1
function rotation_vector(u1, v1) {
let u = normalize(u1);
let v = normalize(v1);
let n = cross(u, v);
let t = Math.acos(dot(u, v));
return `${n[0]} ${n[1]} ${n[2]} ${t}`;
}
function normal_binormal(d) {
const [x, y, z] = d;
let n; // normal
if (x && y) n = normalize([-y, x, 0]);
else if (x && z) n = normalize([-z, 0, x]);
else if (y && z) n = normalize([0, -z, y]);
if(n !== undefined) {
return [n, normalize(cross(n, d))];
}
if (x) return [[0, 1, 0], [0, 0, 1]];
if (y) return [[1, 0, 0], [0, 0, 1]];
if (z) return [[1, 0, 0], [0, 1, 0]];
return [undefined, undefined];
}
function rotation_matrix(d, t) {
let c1, c2, c3;
let rotateX = (t) => [
[1, 0, 0],
[0, Math.cos(t), -Math.sin(t)],
[0, Math.sin(t), Math.cos(t)]
];
if (d[1] == 0 && d[2] == 0) {
return rotateX(t);
} else {
c1 = normalize(d);
c2 = normalize(cross(d, [1, 0, 0]));
c3 = cross(c1, c2);
let S = [
[c1[0], c2[0], c3[0]],
[c1[1], c2[1], c3[1]],
[c1[2], c2[2], c3[2]]
];
let result = math.multiply(S, rotateX(t), math.inv(S));
return result;
}
}
d3 = require('d3-array@2')
math = require("mathjs")
Purpose-built for displays of data
Observable is your go-to platform for exploring data and creating expressive data visualizations. Use reactive JavaScript notebooks for prototyping and a collaborative canvas for visual data exploration and dashboard creation.
