Published
Edited
Mar 24, 2018
1 fork
anchors = [
{x: 20, y: 60},
{x: 80, y: 20}
]
// Computes a weighted sum of `points`, with weights `thetas`.
function pointSum(points, theta) {
let p = {x: 0, y: 0};
for (let i = 0; i < points.length; i++) {
p.x += theta[i] * points[i].x;
p.y += theta[i] * points[i].y;
}
return p;
}
pointsum = {
let theta = Array(n).fill(1);
return pointSum(anchors, theta);
}
midpoint = {
let theta = Array(n).fill(1 / n);
return pointSum(anchors, theta);
}
thetaGrid = cartesianGrid(n, range(-5, 5, 0.2))
{
let points = thetaGrid.map(theta => pointSum(anchors, theta));
return plot(anchors, points);
}
// Checks if the elements of a `theta` vector are non-negative.
function isNonNegative(theta, tol = 0.001) {
return theta.reduce((acc, cur) => acc && (cur >= -tol), true);
}
{
let points = thetaGrid
.filter(theta => isNonNegative(theta))
.map(theta => pointSum(anchors, theta))
return plot(anchors, points)
}
// Checks if the elements of a `theta` vector sum to 1.
function sumsToOne(theta, tol = 0.001) {
var sum = theta.reduce((acc, cur) => acc + cur);
return (sum > 1 - tol && sum < 1 + tol);
}
{
let points = thetaGrid
.filter(theta => sumsToOne(theta))
.map(theta => pointSum(anchors, theta))
return plot(anchors, points)
}
{
let points = thetaGrid
.filter(theta => isNonNegative(theta))
.filter(theta => sumsToOne(theta))
.map(theta => pointSum(anchors, theta))
return plot(anchors, points)
}
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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.
