D3.js 4.0.0 发布，更新如下：
颜色，插值器 和 秤
Colors now have opacity (rgba, hsla, etc.).
New sequential color scales, including Viridis and cyclical Rainbow.
New point and band scales replace ordinal.rangeBands and ordinal.rangePoints.
New basis spline interpolators (e.g., continuous ColorBrewer schemes).
形状 和 布局
Added parameterized Catmull–Rom and natural splines.
New deterministic, extensible velocity Verlet force layout.
New extensible treemap layout; improved squarified treemaps; added binary treemaps.
New d3.stratify for tabular hierarchical data.
New faster, mutable, non-recursive quadtrees.
Voronoi diagrams now expose topological information.
选择，转换， 舒缓 和 定时器
Selections and transitions are now immutable, providing a cleaner interface.
New selection.raise, selection.lower and selection.dispatch methods.
Time is now frozen in the background, avoiding unintended effort.
Timers can now be stopped externally.
Transitions can now interpolate CSS transforms (in addition to SVG transforms).
You can now cancel transitions using selection.interrupt.
Easier transition chaining thanks to new d3.active and changed transition.delay.
Better performance for homogenous transitions (e.g., shared interpolators across elements).
Better state persistence and enforcement for transitions.
更多
Better default axis appearance.
Better brush interaction.
Built-in asynchronous queue for loading files in parallel.
New low-level d3.ticks API.
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引用来自“宅男小何”的评论
d3好像入门挺难的,用起来没其他做图的库简单这个内容还是挺好的，欢迎围观。
http://www.hubwiz.com/course/54fd40cfe564e50d50dcf284/