SVG file from p5 for pen plotters

let a = 0;

function setup() {
  c = min(windowWidth, windowHeight);
  createCanvas((c * 8.5) / 11, c, SVG);
  noFill();
  noLoop();
  stroke(0);
  angleMode(DEGREES);
}
function draw() {
  translate(width / 2, height / 2);
  for (let i = -10; i <= 10; i += 0.2) {
    conchoid(a + i);
    conchoid(a + i);
  }
  a = 9 * sin(50 / 100);
}
function conchoid(a) {
  beginShape();
  n = width / 25;
  for (let i = -70; i < 70; i += 2) {
    y = n * (1 / cos(i) + a * cos(i)) * cos(i);
    x = n * (1 / cos(i) + a * cos(i)) * sin(i);
    curveVertex(x, y);
    if (i % 5 === 0) {
      push();
      translate(x, y);
      rotate(-i);
      pop();
    }
  }
  endShape();
}

function keyPressed() {
  save("drawing.svg");
}