mscoop16

Scatter Plot

This scatter plot displays the relationship between sepal length and sepal width for Iris flowers, with each circle representing a data point from the Iris dataset loaded via `d3.csv`. The visualization uses React components to render SVG elements, with `d3.scaleLinear` handling both axes and `d3.extent` computing the domain. The code employs reusable axis and mark components, styled ticks, and a tooltip showing the formatted sepal length value. Data is fetched asynchronously in a custom `useData` hook.

Jul 12, 2022

Stylized Bar Chart

This stylized bar chart displays the populations of the top ten countries from the UN Population 2019 dataset, rendered as horizontal bars with a teal color scheme and large, clean axis labels. The visualization uses React to manage the component state (via hooks like `useState` and `useEffect`) and D3 v5 functions (`scaleBand`, `scaleLinear`, `csv`, `format`) to handle data loading, scaling, and tick formatting. SVG elements are generated through React components for the axes and marks, with tooltips provided by native SVG `<title>` elements.

Refactored Bar Chart

This example shows a horizontal bar chart of population data for ten countries, using the United Nations 2019 population estimates. The chart displays the bars across a linear scale, with categorical country labels on the left axis and numeric tick marks on the bottom axis. Built with React and D3 v5, the visualization uses d3.csv to load and parse the data, d3.scaleBand for the y-axis, and d3.scaleLinear for the x-axis, rendering all marks as SVG rectangles. The code separates concerns into reusable components for the axes and marks.

Axes With React & D3

This bar chart visualizes the top 10 countries by 2020 population using data from the UN Population dataset, rendered as SVG via React. The code combines React with D3’s `scaleBand` for the categorical y-axis and `scaleLinear` for the numeric x-axis, with `csv` loading the data. Gridlines and tick labels are generated from `xScale.ticks()`, while country names and proportional rectangles are mapped from the data.

The Margin Convention

This example uses the D3 margin convention in a React-based bar chart to display the ten most populous countries from UN population data for 2020. The chart uses `d3.scaleBand` for the y-axis, `d3.scaleLinear` for the x-axis, and SVG `<rect>` elements to render each bar. Data is loaded asynchronously with `d3.csv` and rendered via React's `useState` and `useEffect` hooks. The margin object defines a 20-pixel padding around the SVG canvas, with the chart group translated to that offset using a `transform` attribute.

Pathetic Bar Chart

This example uses React and D3 v5 to render a bar chart of the ten most populous countries in 2020, based on UN population data loaded via `d3.csv`. The `scaleBand` and `scaleLinear` D3 scales map country names to vertical positions and population to horizontal bar widths, while React components generate the SVG `<rect>` elements. The visualization updates from a loading state to the final chart once the asynchronous data fetch completes.

Rendering Data with React & D3

A React application renders CSS named colors from a CSV file as a pie chart using React components for each SVG path. The code uses React hooks (`useState`, `useEffect`) to asynchronously load data with D3's `csv` function, then transforms it with `d3.pie` and draws arcs via `d3.arc`. Each slice is filled with its corresponding hex color value, resulting in a full-circle color wheel. The visualization demonstrates integrating D3’s data-handling utilities with React’s declarative rendering model.

Rendering Data with React

A React component fetches CSS named color data as CSV using D3’s `csv` method and renders each row as a horizontal div whose background color corresponds to the hex value, creating a stacked spectrum. The example demonstrates declarative SVG-free rendering through React’s state hooks, with `useState` and `useEffect` managing asynchronous data loading and a loading state displayed as large text. The data comes from a GitHub gist of MDN’s named colors list.

Loading Data with React & D3

This example demonstrates how to load CSV data into a React application using D3’s `csv` function, then displays a summary of the dataset as text. The visual output shows the data size in kilobytes, row count, and column count, rendered inside a `<pre>` element. The code initializes React state with `useState` and fetches the remote CSS named colors CSV via `useEffect`, while `csvFormat` computes the byte size. All rendering occurs in SVG-less HTML, with D3 v5 and React 16.9 loaded from CDNs.

mcoop Vega-Lite API Template

This example shows the global distribution of religious affiliations across countries, using circle size to encode population and positioning to map country and religion. It renders as an interactive Vega-Lite visualization built programmatically through the vega-lite-api, with data loaded via d3.csv from a remote CSV file. The code customizes axis styling and label appearance through a config object, and uses vega-tooltip for hover details, with a dark theme for readability.

Jun 21, 2022

Loading and Parsing CSV Data

This example demonstrates loading and parsing a CSV file from a remote URL using D3.js v5. It fetches a dataset of CSS named colors and displays key statistics about the file in a large text element. The visualization reports the file size in kilobytes, the total number of rows, and the number of columns. The code uses the `d3.csv` function to asynchronously fetch and parse the data, then leverages `d3.csvFormat` to calculate the file size. An alternative commented-out approach using the Fetch API, `async`/`await`, and `d3.csvParse` is also shown, along with a basic nested-callback example.

Jun 14, 2022

Mouse Follower

A black circle follows the mouse cursor across a white SVG canvas. The React component tracks pointer movement via the `onMouseMove` event and updates the circle’s `cx` and `cy` attributes in response to `clientX` and `clientY` coordinates. It uses `useState` for mouse position and `useCallback` to handle event updates. The example demonstrates declarative SVG rendering with React and the ReactDOM `render` method, with a fixed canvas size of 960 by 500 pixels.

Jun 14, 2022