SG - a library for creating slopegraphs
(see here for live samples)
sg.js creates SVG content, is dependency-free and should work in modern browsers with SVG support.
To use, call SG(jsonData, svgElement, settings). Data is expected as a json array with 'id', 'set' & 'val' attributes. Settings are optional but you most likely will want to set at least textWidth, slopeWidth & height. See sg.html for samples.
So far the fitting logic has so far been kept relatively simple. Improved fitting algorithms & related options are the current focus, trying to provide better layout without killing performance.
and of course, thank you Edward Tufte