The same plot in 14 other libraries — JavaScript: D3.js, Apache ECharts, Highcharts, MUI X Charts; Python: Altair, Bokeh, lets-plot, Matplotlib, Plotly, plotnine, Pygal, Seaborn; R: ggplot2; Julia: Makie.jl. Compare all 15 side by side: Residual Plot in Python, R, Julia and JavaScript.
A residual plot displays the difference between observed and predicted values (residuals) against fitted values in regression analysis. This diagnostic visualization helps identify violations of regression assumptions including non-linearity, heteroscedasticity (non-constant variance), and outliers. A well-fitting model shows residuals randomly scattered around zero with no discernible pattern.

// anyplot.ai
// residual-plot: Residual Plot
// Library: chartjs 4.4.7 | JavaScript 22.23.2
// Quality: 94/100 | Created: 2026-09-05
const t = window.ANYPLOT_TOKENS;
// --- Data (in-memory, deterministic LCG) ------------------------------------
// Simulated linear-regression diagnostics: fitted house-price predictions
// (in $1000s) vs. residuals, with mild heteroscedasticity (variance grows
// with fitted value) so the fan-out pattern is visible.
let seed = 42;
function lcg() {
seed = (seed * 1664525 + 1013904223) % 4294967296;
return seed / 4294967296;
}
function gaussian() {
const u1 = 1 - lcg();
const u2 = lcg();
return Math.sqrt(-2 * Math.log(u1)) * Math.cos(2 * Math.PI * u2);
}
function hexToRgba(hex, alpha) {
const h = hex.replace("#", "");
const r = parseInt(h.substring(0, 2), 16);
const g = parseInt(h.substring(2, 4), 16);
const b = parseInt(h.substring(4, 6), 16);
return `rgba(${r}, ${g}, ${b}, ${alpha})`;
}
const n = 220;
const fitted = [];
const residuals = [];
for (let i = 0; i < n; i++) {
const value = 150 + lcg() * 450; // fitted price, $150k-$600k
const noiseScale = 8 + (value - 150) * 0.05; // heteroscedastic spread
fitted.push(value);
residuals.push(gaussian() * noiseScale);
}
const mean = residuals.reduce((a, b) => a + b, 0) / n;
const variance = residuals.reduce((a, b) => a + (b - mean) ** 2, 0) / n;
const stdDev = Math.sqrt(variance);
const threshold = 2 * stdDev;
const normalPoints = [];
const outlierPoints = [];
for (let i = 0; i < n; i++) {
const point = { x: fitted[i], y: residuals[i] };
if (Math.abs(residuals[i]) > threshold) {
outlierPoints.push(point);
} else {
normalPoints.push(point);
}
}
const xMin = Math.min(...fitted);
const xMax = Math.max(...fitted);
// Rolling-mean smoothing trend (sorted by fitted value) to surface any
// residual non-linearity — optional per spec, adds diagnostic value.
const sortedIdx = fitted.map((_, i) => i).sort((a, b) => fitted[a] - fitted[b]);
const sortedX = sortedIdx.map((i) => fitted[i]);
const sortedY = sortedIdx.map((i) => residuals[i]);
const windowSize = Math.max(15, Math.round(n * 0.12));
const trendPoints = sortedX.map((x, i) => {
const lo = Math.max(0, i - Math.floor(windowSize / 2));
const hi = Math.min(n, i + Math.ceil(windowSize / 2));
const slice = sortedY.slice(lo, hi);
const avg = slice.reduce((a, b) => a + b, 0) / slice.length;
return { x, y: avg };
});
// --- Mount -------------------------------------------------------------------
const canvas = document.createElement("canvas");
document.getElementById("container").appendChild(canvas);
// --- Chart ---------------------------------------------------------------------
new Chart(canvas, {
type: "scatter",
data: {
datasets: [
{
label: "±2σ band",
data: [
{ x: xMin, y: threshold },
{ x: xMax, y: threshold },
],
showLine: true,
borderColor: t.amber,
borderWidth: 1.5,
borderDash: [6, 4],
pointRadius: 0,
fill: "+2",
backgroundColor:
t.pageBg === "#1A1A17" ? "rgba(240,239,232,0.06)" : "rgba(26,26,23,0.04)",
},
{
label: "Zero reference",
data: [
{ x: xMin, y: 0 },
{ x: xMax, y: 0 },
],
showLine: true,
borderColor: t.ink,
borderWidth: 2,
pointRadius: 0,
},
{
label: "−2σ band",
data: [
{ x: xMin, y: -threshold },
{ x: xMax, y: -threshold },
],
showLine: true,
borderColor: t.amber,
borderWidth: 1.5,
borderDash: [6, 4],
pointRadius: 0,
},
{
label: "Residuals",
data: normalPoints,
backgroundColor: hexToRgba(t.palette[0], 0.7),
borderColor: t.pageBg,
borderWidth: 1,
pointRadius: 6,
pointHoverRadius: 7,
},
{
label: "Smoothed trend",
data: trendPoints,
showLine: true,
borderColor: t.palette[1],
borderWidth: 2,
borderDash: [3, 3],
pointRadius: 0,
fill: false,
tension: 0.3,
},
{
label: "Outliers (>2σ)",
data: outlierPoints,
backgroundColor: t.palette[4],
borderColor: t.pageBg,
borderWidth: 1,
pointRadius: 7,
pointStyle: "triangle",
pointHoverRadius: 8,
},
],
},
options: {
responsive: true,
maintainAspectRatio: false,
animation: false,
plugins: {
title: {
display: true,
text: "residual-plot · javascript · chartjs · anyplot.ai",
color: t.ink,
font: { size: 22, weight: "500" },
padding: { bottom: 20 },
},
legend: {
labels: {
color: t.inkSoft,
font: { size: 14 },
filter: (item) => item.text !== "±2σ band" && item.text !== "−2σ band",
},
},
tooltip: { enabled: false },
},
scales: {
x: {
type: "linear",
title: { display: true, text: "Fitted Value ($1,000s)", color: t.ink, font: { size: 16 } },
ticks: { color: t.inkSoft, font: { size: 14 } },
grid: { color: t.grid },
border: { color: t.inkSoft },
},
y: {
title: { display: true, text: "Residual ($1,000s)", color: t.ink, font: { size: 16 } },
ticks: { color: t.inkSoft, font: { size: 14 } },
grid: { color: t.grid },
border: { color: t.inkSoft },
},
},
},
});
Runnable source as JSON, for any HTTP client: https://api.anyplot.ai/specs/residual-plot/chartjs/code. Any spec id and library id listed in llms-full.txt fit the same URL shape; every URL below is complete and callable.
{
"spec_id": "residual-plot",
"language": "javascript",
"library": "chartjs",
"page": "https://anyplot.ai/residual-plot/javascript/chartjs",
"hub": "https://anyplot.ai/residual-plot",
"code_json": "https://api.anyplot.ai/specs/residual-plot/chartjs/code",
"spec_json": "https://api.anyplot.ai/specs/residual-plot",
"render_light_png": "https://storage.googleapis.com/anyplot-images/plots/residual-plot/javascript/chartjs/plot-light.png",
"render_dark_png": "https://storage.googleapis.com/anyplot-images/plots/residual-plot/javascript/chartjs/plot-dark.png",
"interactive_light_html": "https://storage.googleapis.com/anyplot-images/plots/residual-plot/javascript/chartjs/plot-light.html",
"interactive_dark_html": "https://storage.googleapis.com/anyplot-images/plots/residual-plot/javascript/chartjs/plot-dark.html",
"quality_score": 94.0,
"license": "MIT",
"guide": "https://anyplot.ai/llms.txt"
}Part of Residual Plot on anyplot.ai.