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Optimizing Performance for Large Datasets in Line Charts

Explain strategies for optimizing line chart performance when dealing with large datasets, including implementing viewport-based rendering and lazy loading data points as they come into view.
const loadDataPointsInViewPort = (data, viewPortRange) => data.filter(d => d.x >= viewPortRange.start && d.x <= viewPortRange.end);
This function filters the dataset to only include points that fall within the current viewport range. It improves performance by limiting the number of data points being processed and rendered.
const onScroll = (event) => {
  const newViewPortRange = calculateViewPortRange(event);
  const visibleDataPoints = loadDataPointsInViewPort(largeDataSet, newViewPortRange);
  renderLineChart(visibleDataPoints);
};
This event listener function is triggered on scroll. It recalculates the viewport range, fetches the visible data points based on the new range, and re-renders the line chart. This effectively implements lazy loading of data points.
window.addEventListener('scroll', onScroll);
Adds an event listener for the scroll event to dynamically load and render data points based on the current viewport, optimizing performance for large datasets.