let voltage = 2.55;

let current = 10;

let canvasWidth = 600;

let canvasHeight = 550;

let plotWidth = 500;

let plotHeight = 400;

let xOffset = 70;

let yOffset = 50;

let dataPoints = [];

let voltages = [];

let currents = [];

​

function setup() {

  createCanvas(canvasWidth, canvasHeight);

  background('aliceblue');

​

  // Initialize data points

  dataPoints = [

    { v: 2.39, i: 0 },

    { v: 2.52, i: 1 },

    { v: 2.53, i: 2 },

    { v: 2.54, i: 5 },

    { v: 2.55, i: 7 },

    { v: 2.56, i: 10 },

    { v: 2.58, i: 20 },

    { v: 2.60, i: 28 },

    { v: 2.61, i: 34 },

    { v: 2.65, i: 52 },

    { v: 2.68, i: 71 },

    { v: 2.70, i: 88 },

    { v: 2.72, i: 100 },

    { v: 2.74, i: 113 },

    { v: 2.76, i: 124 },

    { v: 2.78, i: 140 }

  ];

​

  // Extract voltages and currents for interpolation

  for (let point of dataPoints) {

    voltages.push(point.v);

    currents.push(point.i);

  }

​

  // Create the voltage slider

  voltageSlider = createSlider(2.35, 2.78, 2.55, 0.01);

  voltageSlider.position(xOffset, plotHeight + yOffset + 50);

  voltageSlider.style('width', `${plotWidth}px`);

}

​

function draw() {

  background('aliceblue');

  fill('snow');

  rect(xOffset, yOffset, plotWidth, plotHeight);

  drawGrid();

  drawAxes();

  drawCurve();

  drawDataPoints();

  drawLabels();

​

  // Get the current voltage value from the slider

  voltage = voltageSlider.value();

​

  // Draw the moving dot

  drawDotOnCurve(voltage);

}

​

function drawGrid() {

  stroke(200); // light gray for grid lines

  strokeWeight(1);

​

  // Vertical grid lines

  for (let x = xOffset; x <= xOffset + plotWidth; x += plotWidth / 10) {

    line(x+9, yOffset, x+9, yOffset + plotHeight);

  }

​

  // Horizontal grid lines

  for (let y = yOffset; y <= yOffset + plotHeight; y += plotHeight / 7) {

    line(xOffset, y, xOffset + plotWidth, y);

  }

}

​

function drawAxes() {

  stroke(0);

  strokeWeight(2);

  // X-axis

  line(xOffset, yOffset + plotHeight, xOffset + plotWidth, yOffset + plotHeight);

  // Y-axis

  line(xOffset, yOffset, xOffset, yOffset + plotHeight);

​

  // X-axis ticks and labels

  textSize(12);

  fill(0);

  noStroke();

  textAlign(CENTER, TOP);

  let xTickStep = 0.05;

  for (let v = 2.35; v <= 2.78; v += xTickStep) {

    let x = map(v, 2.35, 2.78, xOffset, xOffset + plotWidth);

    stroke(0);

    line(x, yOffset + plotHeight, x, yOffset + plotHeight + 5);

    noStroke();

    text(v.toFixed(2), x, yOffset + plotHeight + 8);

  }

​

  // Y-axis ticks and labels

  textAlign(RIGHT, CENTER);

  let yTickStep = 20;

  for (let i = 0; i <= 140; i += yTickStep) {

    let y = map(i, 0, 140, yOffset + plotHeight, yOffset);

    stroke(0);

    line(xOffset - 5, y, xOffset, y);

    noStroke();

    text(i, xOffset - 10, y);

  }

}

​

function drawCurve() {

  noFill();

  stroke('black');

  strokeWeight(2);

  beginShape();

  for (let v = 2.35; v <= 2.78; v += 0.001) {

    let i = interpolateCurrent(v);

    let x = map(v, 2.35, 2.78, xOffset, xOffset + plotWidth);

    let y = map(i, 0, 140, yOffset + plotHeight, yOffset);

    vertex(x, y);

  }

  endShape();

}

​

function drawDataPoints() {

  fill('red');

  noStroke();

  for (let point of dataPoints) {

    let x = map(point.v, 2.35, 2.78, xOffset, xOffset + plotWidth);

    let y = map(point.i, 0, 140, yOffset + plotHeight, yOffset);

    ellipse(x, y, 6, 6);

  }

}

​

function drawDotOnCurve(v) {

  let i = interpolateCurrent(v);

  let x = map(v, 2.35, 2.78, xOffset, xOffset + plotWidth);

  let y = map(i, 0, 140, yOffset + plotHeight, yOffset);

​

  fill('blue');

  noStroke();

  circle(x, y, 10);

}

​

function drawLabels() {

  // Title

  noStroke();

  fill('black');

  textSize(18);

  textAlign(CENTER);

  text("LED Noodle Voltage vs. Current", canvasWidth / 2, 30);

​

  // X-axis label

  textSize(16);

  text("Input Voltage (V)", canvasWidth / 2, plotHeight + 85);

  text("Voltage="+ voltage, 120, plotHeight + 130);

  text("Current(mA)=" + round(interpolateCurrent(voltage), 2), 250, plotHeight + 130);

  // Y-axis label

  push();

  translate(20, canvasHeight / 2);

  rotate(-PI / 2);

  text("Current (mA)", 0, 0);

  pop();

}

​

function interpolateCurrent(v) {

  // Linear interpolation between data points

  if (v <= voltages[0]) return currents[0];

  if (v >= voltages[voltages.length - 1]) return currents[currents.length - 1];

​

  for (let i = 0; i < voltages.length - 1; i++) {

    if (v >= voltages[i] && v <= voltages[i + 1]) {

      let v1 = voltages[i];

      let v2 = voltages[i + 1];

      let i1 = currents[i];

      let i2 = currents[i + 1];

      let fraction = (v - v1) / (v2 - v1);

      return i1 + fraction * (i2 - i1);

    }

  }

  return 0;

}

​