• d3.ticks now tries harder to generate at least one tick. #264

• Fix mutation of user-owned thresholds in d3.bin. #263
• Fix infinite loop when d3.quantile or d3.quickselect is called with invalid arguments. #262

• Add d3.blur. #151
• Add d3.blur2. #151
• Add d3.blurImage. #151
• Add d3.medianIndex. #159
• Add d3.quantileIndex. #159

• Fix incorrect behavior of d3.bisector when given an asymmetric comparator. #249 #250

• Fix crash in d3.bin. Thanks, @weiglemc! #248

• Fix off-by-one bin assignment due to rounding error in d3.bin. #247

• Significantly improve the performance of d3.bin. #220
• Tweak the implementation of d3.thresholdScott. a8429c4

• Fix the implementation of d3.thresholdScott. #246

• d3.rank can now take a comparator in addition to an accessor. #237
• d3.rank, d3.sort, d3.bisector, and d3.groupSort now require comparators to have exactly two arguments. #238

• Add d3.rank. #228

• Don’t mangle InternMap or InternSet in the generated UMD bundle.

• Adopt interning for set operations. #231
• Fix InternSet and InternMap’s delete operation. mbostock/internmap@2.0.2

• Fix d3.sort, d3.bisector, and related methods to handle undefined order. #227 #217
• Avoid anonymous default exports (to assist hot module reload tools). #226
• Update dependencies.

• Update dependencies.
• Make build reproducible.

• Adopt type: module. #202
• Add d3.mode. #205
• Add d3.flatGroup and d3.flatRollup. #196
• d3.ascending and d3.descending no longer consider null comparable. #210
• d3.bin now ignores nulls. #204

This package now requires Node.js 12 or higher. For more, please read Sindre Sorhus’s FAQ.

• Fix rounding error in d3.ticks. #199

• Add d3.fcumsum. Thanks, @fil!
• Fix crash passing null to d3.InternMap or d3.InternSet constructor.

• Add d3.groupSort.
• Allow d3.sort to take multiple accessors.

• Add d3.InternMap.
• Add d3.InternSet.
• Change d3.group, d3.rollup et al. to use InternMap.

• Fix last bin with d3.bin when the values are not numbers.
• Fix last bin with d3.bin when the tick increment is fractional.

• d3.sort now may accept an accessor. #183
• Fix zero-width last bin with d3.bin. #177

• Add d3.nice.
• Add d3.every.
• Add d3.some.
• Add d3.filter.
• Add d3.map.
• Add d3.reduce.
• Add d3.reverse.
• Add d3.sort.
• Add d3.difference.
• Add d3.disjoint.
• Add d3.intersection.
• Add d3.superset.
• Add d3.subset.
• Add d3.union.
• Fix d3.bin to nice the domain by default, ensuring uniform bin widths.

• Fix imprecision with bin.thresholds(count). #169

• Add d3.bisectCenter. #138
• Add d3.shuffler. #167
• Fix off-by-one with hi in bisector.center.

• Add d3.index.
• Add d3.indexes.
• Add bisector.center.

• Fix: d3.ticks sometimes incorrectly returned ticks outside the domain (#162)

• Add d3.fsum.
• Add d3.Adder.

• Add d3.cumsum. Thanks, @Fil! #102

• Greatly improve the performance of d3.median. Thanks, @Fil and @jheer!

• Avoid an array.sort bug in Safari. #123
• Fix bin thresholds to ignore NaN input.

• Fix d3.count to ignore non-number input.

• Add d3.greatest.
• Add d3.greatestIndex.
• Add d3.quantileSorted.
• Change d3.quantile to accept iterables and non-sorted inputs.

• Add d3.groups.
• Add d3.rollups.
• Allow d3.least and d3.leastIndex to accept accessors.

• Add d3.bin.
• Add d3.count. Thanks, @Fil!
• Add d3.minIndex.
• Add d3.maxIndex.
• Add d3.least.
• Add d3.leastIndex.
• Deprecate d3.scan; use d3.leastIndex instead.
• Deprecate d3.histogram; use d3.bin instead.
• Fix d3.permute to accept an iterable.
• Fix internal ES imports.

• Fix histogram(iterable).

• Fix an infinite loop in d3.cross. Thanks, @jviide!

• Optimize and fix iteration in d3.cross. Thanks, @jviide!

See https://observablehq.com/@d3/d3-array-2-0 for details.

• Add d3.quickselect.
• Add d3.group.
• Add d3.rollup.
• Rewrite d3.median to use quickselect.
• Accept iterables (not just arrays) where relevant.
• Allow more than two iterables for d3.cross.

Note: this release adopts ES2015 language features such as for-of and drops support for older browsers, including IE. If you need to support pre-ES2015 environments, you should stick with d3-array 1.x or use a transpiler.

• Fix upper histogram bin threshold in some cases. Thanks, @hiraku! (#65)

• Fix d3.ticks when start is equal to stop and count is positive. (d3/d3-scale#113)

• Add d3.tickIncrement. (#45)
• Fix d3.ticks to always return the most-precise representable values in IEEE 754!
• Fix histogram.thresholds to retain thresholds equal to the domain’s upper bound. (#54)
• Document that histogram.thresholds ignores thresholds outside the domain’s bounds.
• Improve the readability of the code.

• Add d3.cross. (#50)
• Allow d3.pairs to take an optional reducer.

• Add module entry point to package.json.

• First stable release!

Changes since D3 3.x

The new d3.scan method performs a linear scan of an array, returning the index of the least element according to the specified comparator. This is similar to d3.min and d3.max, except you can use it to find the position of an extreme element, rather than just calculate an extreme value.

var data = [
  {name: "Alice", value: 2},
  {name: "Bob", value: 3},
  {name: "Carol", value: 1},
  {name: "Dwayne", value: 5}
];

var i = d3.scan(data, function(a, b) { return a.value - b.value; }); // 2
data[i]; // {name: "Carol", value: 1}

The new d3.ticks and d3.tickStep methods are useful for generating human-readable numeric ticks. These methods are a low-level alternative to continuous.ticks from d3-scale. The new implementation is also more accurate, returning the optimal number of ticks as measured by relative error.

var ticks = d3.ticks(0, 10, 5); // [0, 2, 4, 6, 8, 10]

The d3.range method no longer makes an elaborate attempt to avoid floating-point error when step is not an integer. The returned values are strictly defined as start + i * step, where i is an integer. (Learn more about floating point math.) d3.range returns the empty array for infinite ranges, rather than throwing an error.

The method signature for optional accessors has been changed to be more consistent with array methods such as array.forEach: the accessor is passed the current element (d), the index (i), and the array (data), with this as undefined. This affects d3.min, d3.max, d3.extent, d3.sum, d3.mean, d3.median, d3.quantile, d3.variance and d3.deviation. The d3.quantile method previously did not take an accessor. Some methods with optional arguments now treat those arguments as missing if they are null or undefined, rather than strictly checking arguments.length.

The new d3.histogram API replaces d3.layout.histogram. Rather than exposing bin.x and bin.dx on each returned bin, the histogram exposes bin.x0 and bin.x1, guaranteeing that bin.x0 is exactly equal to bin.x1 on the preceeding bin. The “frequency” and “probability” modes are no longer supported; each bin is simply an array of elements from the input data, so bin.length is equal to D3 3.x’s bin.y in frequency mode. To compute a probability distribution, divide the number of elements in each bin by the total number of elements.

The histogram.range method has been renamed histogram.domain for consistency with scales. The histogram.bins method has been renamed histogram.thresholds, and no longer accepts an upper value: n thresholds will produce n + 1 bins. If you specify a desired number of bins rather than thresholds, d3.histogram now uses d3.ticks to compute nice bin thresholds. In addition to the default Sturges’ formula, D3 now implements the Freedman-Diaconis rule and Scott’s normal reference rule.

See CHANGES for all D3 changes since 3.x.

• d3.histogram no longer coerces all inputs to numbers (#34).
• d3.thresholdFreedmanDiaconis now sorts a copy of values, rather than sorting in-place.

• Export to the global d3 in vanilla environments (d3/d3#2840).

• Move keys, values, entries, map, set, and nest to d3-collection.

• Optimize sum.

• Add ticks and tickStep.
• The histogram generator now generates nicely-rounded bins by default.

• The set constructor now takes an optional accessor function.

• Fix name of generated d3_array global.