main repo

node_modules/d3-interpolate/LICENSE

@@ -0,0 +1,13 @@
+Copyright 2010-2021 Mike Bostock
+
+Permission to use, copy, modify, and/or distribute this software for any purpose
+with or without fee is hereby granted, provided that the above copyright notice
+and this permission notice appear in all copies.
+
+THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
+REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
+FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
+INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
+OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF
+THIS SOFTWARE.

node_modules/d3-interpolate/README.md

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+# d3-interpolate
+
+This module provides a variety of interpolation methods for blending between two values. Values may be numbers, colors, strings, arrays, or even deeply-nested objects. For example:
+
+```js
+const i = d3.interpolateNumber(10, 20);
+i(0.0); // 10
+i(0.2); // 12
+i(0.5); // 15
+i(1.0); // 20
+```
+
+The returned function `i` is called an *interpolator*. Given a starting value *a* and an ending value *b*, it takes a parameter *t* in the domain [0, 1] and returns the corresponding interpolated value between *a* and *b*. An interpolator typically returns a value equivalent to *a* at *t* = 0 and a value equivalent to *b* at *t* = 1.
+
+You can interpolate more than just numbers. To find the perceptual midpoint between steelblue and brown:
+
+```js
+d3.interpolateLab("steelblue", "brown")(0.5); // "rgb(142, 92, 109)"
+```
+
+Here’s a more elaborate example demonstrating type inference used by [interpolate](#interpolate):
+
+```js
+const i = d3.interpolate({colors: ["red", "blue"]}, {colors: ["white", "black"]});
+i(0.0); // {colors: ["rgb(255, 0, 0)", "rgb(0, 0, 255)"]}
+i(0.5); // {colors: ["rgb(255, 128, 128)", "rgb(0, 0, 128)"]}
+i(1.0); // {colors: ["rgb(255, 255, 255)", "rgb(0, 0, 0)"]}
+```
+
+Note that the generic value interpolator detects not only nested objects and arrays, but also color strings and numbers embedded in strings!
+
+## Installing
+
+If you use npm, `npm install d3-interpolate`. You can also download the [latest release on GitHub](https://github.com/d3/d3-interpolate/releases/latest). For vanilla HTML in modern browsers, import d3-interpolate from Skypack:
+
+```html
+<script type="module">
+
+import {interpolateRgb} from "https://cdn.skypack.dev/d3-interpolate@3";
+
+const interpolate = interpolateRgb("steelblue", "brown");
+
+</script>
+```
+
+For legacy environments, you can load d3-interpolate’s UMD bundle from an npm-based CDN such as jsDelivr; a `d3` global is exported. (If using [color interpolation](#color-spaces), also load [d3-color](https://github.com/d3/d3-color).)
+
+```html
+<script src="https://cdn.jsdelivr.net/npm/d3-color@3"></script>
+<script src="https://cdn.jsdelivr.net/npm/d3-interpolate@3"></script>
+<script>
+
+const interpolate = d3.interpolateRgb("steelblue", "brown");
+
+</script>
+```
+
+## API Reference
+
+<a name="interpolate" href="#interpolate">#</a> d3.<b>interpolate</b>(<i>a</i>, <i>b</i>) · [Source](https://github.com/d3/d3-interpolate/blob/master/src/value.js), [Examples](https://observablehq.com/@d3/d3-interpolate)
+
+Returns an interpolator between the two arbitrary values *a* and *b*. The interpolator implementation is based on the type of the end value *b*, using the following algorithm:
+
+1. If *b* is null, undefined or a boolean, use the constant *b*.
+2. If *b* is a number, use [interpolateNumber](#interpolateNumber).
+3. If *b* is a [color](https://github.com/d3/d3-color/blob/master/README.md#color) or a string coercible to a color, use [interpolateRgb](#interpolateRgb).
+4. If *b* is a [date](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date), use [interpolateDate](#interpolateDate).
+5. If *b* is a string, use [interpolateString](#interpolateString).
+6. If *b* is a [typed array](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray) of numbers, use [interpolateNumberArray](#interpolateNumberArray).
+7. If *b* is a generic [array](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/isArray), use [interpolateArray](#interpolateArray).
+8. If *b* is coercible to a number, use [interpolateNumber](#interpolateNumber).
+9. Use [interpolateObject](#interpolateObject).
+
+Based on the chosen interpolator, *a* is coerced to the suitable corresponding type.
+
+<a name="interpolateNumber" href="#interpolateNumber">#</a> d3.<b>interpolateNumber</b>(<i>a</i>, <i>b</i>) · [Source](https://github.com/d3/d3-interpolate/blob/master/src/number.js), [Examples](https://observablehq.com/@d3/d3-interpolatenumber)
+
+Returns an interpolator between the two numbers *a* and *b*. The returned interpolator is equivalent to:
+
+```js
+function interpolator(t) {
+  return a * (1 - t) + b * t;
+}
+```
+
+Caution: avoid interpolating to or from the number zero when the interpolator is used to generate a string. When very small values are stringified, they may be converted to scientific notation, which is an invalid attribute or style property value in older browsers. For example, the number `0.0000001` is converted to the string `"1e-7"`. This is particularly noticeable with interpolating opacity. To avoid scientific notation, start or end the transition at 1e-6: the smallest value that is not stringified in scientific notation.
+
+<a name="interpolateRound" href="#interpolateRound">#</a> d3.<b>interpolateRound</b>(<i>a</i>, <i>b</i>) · [Source](https://github.com/d3/d3-interpolate/blob/master/src/round.js), [Examples](https://observablehq.com/@d3/d3-interpolatenumber)
+
+Returns an interpolator between the two numbers *a* and *b*; the interpolator is similar to [interpolateNumber](#interpolateNumber), except it will round the resulting value to the nearest integer.
+
+<a name="interpolateString" href="#interpolateString">#</a> d3.<b>interpolateString</b>(<i>a</i>, <i>b</i>) · [Source](https://github.com/d3/d3-interpolate/blob/master/src/string.js), [Examples](https://observablehq.com/@d3/d3-interpolatestring)
+
+Returns an interpolator between the two strings *a* and *b*. The string interpolator finds numbers embedded in *a* and *b*, where each number is of the form understood by JavaScript. A few examples of numbers that will be detected within a string: `-1`, `42`, `3.14159`, and `6.0221413e+23`.
+
+For each number embedded in *b*, the interpolator will attempt to find a corresponding number in *a*. If a corresponding number is found, a numeric interpolator is created using [interpolateNumber](#interpolateNumber). The remaining parts of the string *b* are used as a template: the static parts of the string *b* remain constant for the interpolation, with the interpolated numeric values embedded in the template.
+
+For example, if *a* is `"300 12px sans-serif"`, and *b* is `"500 36px Comic-Sans"`, two embedded numbers are found. The remaining static parts (of string *b*) are a space between the two numbers (`" "`), and the suffix (`"px Comic-Sans"`). The result of the interpolator at *t* = 0.5 is `"400 24px Comic-Sans"`.
+
+<a name="interpolateDate" href="#interpolateDate">#</a> d3.<b>interpolateDate</b>(<i>a</i>, <i>b</i>) · [Source](https://github.com/d3/d3-interpolate/blob/master/src/date.js), [Examples](https://observablehq.com/@d3/d3-interpolatedate)
+
+Returns an interpolator between the two [dates](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date) *a* and *b*.
+
+Note: **no defensive copy** of the returned date is created; the same Date instance is returned for every evaluation of the interpolator. No copy is made for performance reasons; interpolators are often part of the inner loop of [animated transitions](https://github.com/d3/d3-transition).
+
+<a name="interpolateArray" href="#interpolateArray">#</a> d3.<b>interpolateArray</b>(<i>a</i>, <i>b</i>) · [Source](https://github.com/d3/d3-interpolate/blob/master/src/array.js), [Examples](https://observablehq.com/@d3/d3-interpolateobject)
+
+Returns an interpolator between the two arrays *a* and *b*. If *b* is a typed array (e.g., Float64Array), [interpolateNumberArray](#interpolateNumberArray) is called instead.
+
+Internally, an array template is created that is the same length as *b*. For each element in *b*, if there exists a corresponding element in *a*, a generic interpolator is created for the two elements using [interpolate](#interpolate). If there is no such element, the static value from *b* is used in the template. Then, for the given parameter *t*, the template’s embedded interpolators are evaluated. The updated array template is then returned.
+
+For example, if *a* is the array `[0, 1]` and *b* is the array `[1, 10, 100]`, then the result of the interpolator for *t* = 0.5 is the array `[0.5, 5.5, 100]`.
+
+Note: **no defensive copy** of the template array is created; modifications of the returned array may adversely affect subsequent evaluation of the interpolator. No copy is made for performance reasons; interpolators are often part of the inner loop of [animated transitions](https://github.com/d3/d3-transition).
+
+<a name="interpolateNumberArray" href="#interpolateNumberArray">#</a> d3.<b>interpolateNumberArray</b>(<i>a</i>, <i>b</i>) · [Source](https://github.com/d3/d3-interpolate/blob/master/src/numberArray.js), [Examples](https://observablehq.com/@d3/d3-interpolatenumberarray)
+
+Returns an interpolator between the two arrays of numbers *a* and *b*. Internally, an array template is created that is the same type and length as *b*. For each element in *b*, if there exists a corresponding element in *a*, the values are directly interpolated in the array template. If there is no such element, the static value from *b* is copied. The updated array template is then returned.
+
+Note: For performance reasons, **no defensive copy** is made of the template array and the arguments *a* and *b*; modifications of these arrays may affect subsequent evaluation of the interpolator.
+
+<a name="interpolateObject" href="#interpolateObject">#</a> d3.<b>interpolateObject</b>(<i>a</i>, <i>b</i>) · [Source](https://github.com/d3/d3-interpolate/blob/master/src/object.js), [Examples](https://observablehq.com/@d3/d3-interpolateobject)
+
+Returns an interpolator between the two objects *a* and *b*. Internally, an object template is created that has the same properties as *b*. For each property in *b*, if there exists a corresponding property in *a*, a generic interpolator is created for the two elements using [interpolate](#interpolate). If there is no such property, the static value from *b* is used in the template. Then, for the given parameter *t*, the template's embedded interpolators are evaluated and the updated object template is then returned.
+
+For example, if *a* is the object `{x: 0, y: 1}` and *b* is the object `{x: 1, y: 10, z: 100}`, the result of the interpolator for *t* = 0.5 is the object `{x: 0.5, y: 5.5, z: 100}`.
+
+Object interpolation is particularly useful for *dataspace interpolation*, where data is interpolated rather than attribute values. For example, you can interpolate an object which describes an arc in a pie chart, and then use [d3.arc](https://github.com/d3/d3-shape/blob/master/README.md#arc) to compute the new SVG path data.
+
+Note: **no defensive copy** of the template object is created; modifications of the returned object may adversely affect subsequent evaluation of the interpolator. No copy is made for performance reasons; interpolators are often part of the inner loop of [animated transitions](https://github.com/d3/d3-transition).
+
+<a name="interpolateTransformCss" href="#interpolateTransformCss">#</a> d3.<b>interpolateTransformCss</b>(<i>a</i>, <i>b</i>) · [Source](https://github.com/d3/d3-interpolate/blob/master/src/transform/index.js#L62), [Examples](https://observablehq.com/@d3/d3-interpolatetransformcss)
+
+Returns an interpolator between the two 2D CSS transforms represented by *a* and *b*. Each transform is decomposed to a standard representation of translate, rotate, *x*-skew and scale; these component transformations are then interpolated. This behavior is standardized by CSS: see [matrix decomposition for animation](http://www.w3.org/TR/css3-2d-transforms/#matrix-decomposition).
+
+<a name="interpolateTransformSvg" href="#interpolateTransformSvg">#</a> d3.<b>interpolateTransformSvg</b>(<i>a</i>, <i>b</i>) · [Source](https://github.com/d3/d3-interpolate/blob/master/src/transform/index.js#L63), [Examples](https://observablehq.com/@d3/d3-interpolatetransformcss)
+
+Returns an interpolator between the two 2D SVG transforms represented by *a* and *b*. Each transform is decomposed to a standard representation of translate, rotate, *x*-skew and scale; these component transformations are then interpolated. This behavior is standardized by CSS: see [matrix decomposition for animation](http://www.w3.org/TR/css3-2d-transforms/#matrix-decomposition).
+
+<a name="interpolateZoom" href="#interpolateZoom">#</a> d3.<b>interpolateZoom</b>(<i>a</i>, <i>b</i>) · [Source](https://github.com/d3/d3-interpolate/blob/master/src/zoom.js), [Examples](https://observablehq.com/@d3/d3-interpolatezoom)
+
+Returns an interpolator between the two views *a* and *b* of a two-dimensional plane, based on [“Smooth and efficient zooming and panning”](http://www.win.tue.nl/~vanwijk/zoompan.pdf) by Jarke J. van Wijk and Wim A.A. Nuij. Each view is defined as an array of three numbers: *cx*, *cy* and *width*. The first two coordinates *cx*, *cy* represent the center of the viewport; the last coordinate *width* represents the size of the viewport.
+
+The returned interpolator exposes a *duration* property which encodes the recommended transition duration in milliseconds. This duration is based on the path length of the curved trajectory through *x,y* space. If you want a slower or faster transition, multiply this by an arbitrary scale factor (<i>V</i> as described in the original paper).
+
+<a name="interpolateZoom_rho" href="#interpolateZoom_rho">#</a> *interpolateZoom*.<b>rho</b>(<i>rho</i>) · [Source](https://github.com/d3/d3-interpolate/blob/master/src/zoom.js)<!-- , [Examples](https://observablehq.com/@d3/interpolatezoom-rho) -->
+
+Given a [zoom interpolator](#interpolateZoom), returns a new zoom interpolator using the specified curvature *rho*. When *rho* is close to 0, the interpolator is almost linear. The default curvature is sqrt(2).
+
+<a name="interpolateDiscrete" href="#interpolateDiscrete">#</a> d3.<b>interpolateDiscrete</b>(<i>values</i>) · [Source](https://github.com/d3/d3-interpolate/blob/master/src/discrete.js), [Examples](https://observablehq.com/@d3/d3-interpolatediscrete)
+
+Returns a discrete interpolator for the given array of *values*. The returned interpolator maps *t* in [0, 1 / *n*) to *values*[0], *t* in [1 / *n*, 2 / *n*) to *values*[1], and so on, where *n* = *values*.length. In effect, this is a lightweight [quantize scale](https://github.com/d3/d3-scale/blob/master/README.md#quantize-scales) with a fixed domain of [0, 1].
+
+### Sampling
+
+<a name="quantize" href="#quantize">#</a> d3.<b>quantize</b>(<i>interpolator</i>, <i>n</i>) · [Source](https://github.com/d3/d3-interpolate/blob/master/src/quantize.js), [Examples](https://observablehq.com/@d3/d3-quantize)
+
+Returns *n* uniformly-spaced samples from the specified *interpolator*, where *n* is an integer greater than one. The first sample is always at *t* = 0, and the last sample is always at *t* = 1. This can be useful in generating a fixed number of samples from a given interpolator, such as to derive the range of a [quantize scale](https://github.com/d3/d3-scale/blob/master/README.md#quantize-scales) from a [continuous interpolator](https://github.com/d3/d3-scale-chromatic/blob/master/README.md#interpolateWarm).
+
+Caution: this method will not work with interpolators that do not return defensive copies of their output, such as [d3.interpolateArray](#interpolateArray), [d3.interpolateDate](#interpolateDate) and [d3.interpolateObject](#interpolateObject). For those interpolators, you must wrap the interpolator and create a copy for each returned value.
+
+### Color Spaces
+
+<a name="interpolateRgb" href="#interpolateRgb">#</a> d3.<b>interpolateRgb</b>(<i>a</i>, <i>b</i>) · [Source](https://github.com/d3/d3-interpolate/blob/master/src/rgb.js), [Examples](https://observablehq.com/@d3/working-with-color)
+
+<img src="https://raw.githubusercontent.com/d3/d3-interpolate/master/img/rgb.png" width="100%" height="40" alt="rgb">
+
+Or, with a corrected [gamma](#interpolate_gamma) of 2.2:
+
+<img src="https://raw.githubusercontent.com/d3/d3-interpolate/master/img/rgbGamma.png" width="100%" height="40" alt="rgbGamma">
+
+Returns an RGB color space interpolator between the two colors *a* and *b* with a configurable [gamma](#interpolate_gamma). If the gamma is not specified, it defaults to 1.0. The colors *a* and *b* need not be in RGB; they will be converted to RGB using [d3.rgb](https://github.com/d3/d3-color/blob/master/README.md#rgb). The return value of the interpolator is an RGB string.
+
+<a href="#interpolateRgbBasis" name="interpolateRgbBasis">#</a> d3.<b>interpolateRgbBasis</b>(<i>colors</i>) · [Source](https://github.com/d3/d3-interpolate/blob/master/src/rgb.js#L54), [Examples](https://observablehq.com/@d3/working-with-color)
+
+Returns a uniform nonrational B-spline interpolator through the specified array of *colors*, which are converted to [RGB color space](https://github.com/d3/d3-color/blob/master/README.md#rgb). Implicit control points are generated such that the interpolator returns *colors*[0] at *t* = 0 and *colors*[*colors*.length - 1] at *t* = 1. Opacity interpolation is not currently supported. See also [d3.interpolateBasis](#interpolateBasis), and see [d3-scale-chromatic](https://github.com/d3/d3-scale-chromatic) for examples.
+
+<a href="#interpolateRgbBasisClosed" name="interpolateRgbBasisClosed">#</a> d3.<b>interpolateRgbBasisClosed</b>(<i>colors</i>) · [Source](https://github.com/d3/d3-interpolate/blob/master/src/rgb.js#L55), [Examples](https://observablehq.com/@d3/working-with-color)
+
+Returns a uniform nonrational B-spline interpolator through the specified array of *colors*, which are converted to [RGB color space](https://github.com/d3/d3-color/blob/master/README.md#rgb). The control points are implicitly repeated such that the resulting spline has cyclical C² continuity when repeated around *t* in [0,1]; this is useful, for example, to create cyclical color scales. Opacity interpolation is not currently supported. See also [d3.interpolateBasisClosed](#interpolateBasisClosed), and see [d3-scale-chromatic](https://github.com/d3/d3-scale-chromatic) for examples.
+
+<a name="interpolateHsl" href="#interpolateHsl">#</a> d3.<b>interpolateHsl</b>(<i>a</i>, <i>b</i>) · [Source](https://github.com/d3/d3-interpolate/blob/master/src/hsl.js), [Examples](https://observablehq.com/@d3/working-with-color)
+
+<img src="https://raw.githubusercontent.com/d3/d3-interpolate/master/img/hsl.png" width="100%" height="40" alt="hsl">
+
+Returns an HSL color space interpolator between the two colors *a* and *b*. The colors *a* and *b* need not be in HSL; they will be converted to HSL using [d3.hsl](https://github.com/d3/d3-color/blob/master/README.md#hsl). If either color’s hue or saturation is NaN, the opposing color’s channel value is used. The shortest path between hues is used. The return value of the interpolator is an RGB string.
+
+<a name="interpolateHslLong" href="#interpolateHslLong">#</a> d3.<b>interpolateHslLong</b>(<i>a</i>, <i>b</i>) · [Source](https://github.com/d3/d3-interpolate/blob/master/src/hsl.js#L21), [Examples](https://observablehq.com/@d3/working-with-color)
+
+<img src="https://raw.githubusercontent.com/d3/d3-interpolate/master/img/hslLong.png" width="100%" height="40" alt="hslLong">
+
+Like [interpolateHsl](#interpolateHsl), but does not use the shortest path between hues.
+
+<a name="interpolateLab" href="#interpolateLab">#</a> d3.<b>interpolateLab</b>(<i>a</i>, <i>b</i>) · [Source](https://github.com/d3/d3-interpolate/blob/master/src/lab.js), [Examples](https://observablehq.com/@d3/working-with-color)
+
+<img src="https://raw.githubusercontent.com/d3/d3-interpolate/master/img/lab.png" width="100%" height="40" alt="lab">
+
+Returns a [CIELAB color space](https://en.wikipedia.org/wiki/Lab_color_space#CIELAB) interpolator between the two colors *a* and *b*. The colors *a* and *b* need not be in CIELAB; they will be converted to CIELAB using [d3.lab](https://github.com/d3/d3-color/blob/master/README.md#lab). The return value of the interpolator is an RGB string.
+
+<a name="interpolateHcl" href="#interpolateHcl">#</a> d3.<b>interpolateHcl</b>(<i>a</i>, <i>b</i>) · [Source](https://github.com/d3/d3-interpolate/blob/master/src/hcl.js), [Examples](https://observablehq.com/@d3/working-with-color)
+
+<img src="https://raw.githubusercontent.com/d3/d3-interpolate/master/img/hcl.png" width="100%" height="40" alt="hcl">
+
+Returns a [CIELCh<sub>ab</sub> color space](https://en.wikipedia.org/wiki/CIELAB_color_space#Cylindrical_representation:_CIELCh_or_CIEHLC) interpolator between the two colors *a* and *b*. The colors *a* and *b* need not be in CIELCh<sub>ab</sub>; they will be converted to CIELCh<sub>ab</sub> using [d3.hcl](https://github.com/d3/d3-color/blob/master/README.md#hcl). If either color’s hue or chroma is NaN, the opposing color’s channel value is used. The shortest path between hues is used. The return value of the interpolator is an RGB string.
+
+<a name="interpolateHclLong" href="#interpolateHclLong">#</a> d3.<b>interpolateHclLong</b>(<i>a</i>, <i>b</i>) · [Source](https://github.com/d3/d3-interpolate/blob/master/src/hcl.js#L21), [Examples](https://observablehq.com/@d3/working-with-color)
+
+<img src="https://raw.githubusercontent.com/d3/d3-interpolate/master/img/hclLong.png" width="100%" height="40" alt="hclLong">
+
+Like [interpolateHcl](#interpolateHcl), but does not use the shortest path between hues.
+
+<a name="interpolateCubehelix" href="#interpolateCubehelix">#</a> d3.<b>interpolateCubehelix</b>(<i>a</i>, <i>b</i>) · [Source](https://github.com/d3/d3-interpolate/blob/master/src/cubehelix.js), [Examples](https://observablehq.com/@d3/working-with-color)
+
+<img src="https://raw.githubusercontent.com/d3/d3-interpolate/master/img/cubehelix.png" width="100%" height="40" alt="cubehelix">
+
+Or, with a [gamma](#interpolate_gamma) of 3.0 to emphasize high-intensity values:
+
+<img src="https://raw.githubusercontent.com/d3/d3-interpolate/master/img/cubehelixGamma.png" width="100%" height="40" alt="cubehelixGamma">
+
+Returns a Cubehelix color space interpolator between the two colors *a* and *b* using a configurable [gamma](#interpolate_gamma). If the gamma is not specified, it defaults to 1.0. The colors *a* and *b* need not be in Cubehelix; they will be converted to Cubehelix using [d3.cubehelix](https://github.com/d3/d3-color/blob/master/README.md#cubehelix). If either color’s hue or saturation is NaN, the opposing color’s channel value is used. The shortest path between hues is used. The return value of the interpolator is an RGB string.
+
+<a name="interpolateCubehelixLong" href="#interpolateCubehelixLong">#</a> d3.<b>interpolateCubehelixLong</b>(<i>a</i>, <i>b</i>) · [Source](https://github.com/d3/d3-interpolate/blob/master/src/cubehelix.js#L29), [Examples](https://observablehq.com/@d3/working-with-color)
+
+<img src="https://raw.githubusercontent.com/d3/d3-interpolate/master/img/cubehelixLong.png" width="100%" height="40" alt="cubehelixLong">
+
+Or, with a [gamma](#interpolate_gamma) of 3.0 to emphasize high-intensity values:
+
+<img src="https://raw.githubusercontent.com/d3/d3-interpolate/master/img/cubehelixGammaLong.png" width="100%" height="40" alt="cubehelixGammaLong">
+
+Like [interpolateCubehelix](#interpolateCubehelix), but does not use the shortest path between hues.
+
+<a name="interpolate_gamma" href="#interpolate_gamma">#</a> <i>interpolate</i>.<b>gamma</b>(<i>gamma</i>)
+
+Given that *interpolate* is one of [interpolateRgb](#interpolateRgb), [interpolateCubehelix](#interpolateCubehelix) or [interpolateCubehelixLong](#interpolateCubehelixLong), returns a new interpolator factory of the same type using the specified *gamma*. For example, to interpolate from purple to orange with a gamma of 2.2 in RGB space:
+
+```js
+const interpolator = d3.interpolateRgb.gamma(2.2)("purple", "orange");
+```
+
+See Eric Brasseur’s article, [Gamma error in picture scaling](http://www.ericbrasseur.org/gamma.html), for more on gamma correction.
+
+<a name="interpolateHue" href="#interpolateHue">#</a> d3.<b>interpolateHue</b>(<i>a</i>, <i>b</i>) · [Source](https://github.com/d3/d3-interpolate/blob/master/src/hue.js), [Examples](https://observablehq.com/@d3/working-with-color)
+
+Returns an interpolator between the two hue angles *a* and *b*. If either hue is NaN, the opposing value is used. The shortest path between hues is used. The return value of the interpolator is a number in [0, 360).
+
+### Splines
+
+Whereas standard interpolators blend from a starting value *a* at *t* = 0 to an ending value *b* at *t* = 1, spline interpolators smoothly blend multiple input values for *t* in [0,1] using piecewise polynomial functions. Only cubic uniform nonrational [B-splines](https://en.wikipedia.org/wiki/B-spline) are currently supported, also known as basis splines.
+
+<a href="#interpolateBasis" name="interpolateBasis">#</a> d3.<b>interpolateBasis</b>(<i>values</i>) · [Source](https://github.com/d3/d3-interpolate/blob/master/src/basis.js), [Examples](https://observablehq.com/@d3/d3-interpolatebasis)
+
+Returns a uniform nonrational B-spline interpolator through the specified array of *values*, which must be numbers. Implicit control points are generated such that the interpolator returns *values*[0] at *t* = 0 and *values*[*values*.length - 1] at *t* = 1. See also [d3.curveBasis](https://github.com/d3/d3-shape/blob/master/README.md#curveBasis).
+
+<a href="#interpolateBasisClosed" name="interpolateBasisClosed">#</a> d3.<b>interpolateBasisClosed</b>(<i>values</i>) · [Source](https://github.com/d3/d3-interpolate/blob/master/src/basisClosed.js), [Examples](https://observablehq.com/@d3/d3-interpolatebasis)
+
+Returns a uniform nonrational B-spline interpolator through the specified array of *values*, which must be numbers. The control points are implicitly repeated such that the resulting one-dimensional spline has cyclical C² continuity when repeated around *t* in [0,1]. See also [d3.curveBasisClosed](https://github.com/d3/d3-shape/blob/master/README.md#curveBasisClosed).
+
+### Piecewise
+
+<a name="piecewise" href="#piecewise">#</a> d3.<b>piecewise</b>([<i>interpolate</i>, ]<i>values</i>) · [Source](https://github.com/d3/d3-interpolate/blob/master/src/piecewise.js), [Examples](https://observablehq.com/@d3/d3-piecewise)
+
+Returns a piecewise interpolator, composing interpolators for each adjacent pair of *values*. The returned interpolator maps *t* in [0, 1 / (*n* - 1)] to *interpolate*(*values*[0], *values*[1]), *t* in [1 / (*n* - 1), 2 / (*n* - 1)] to *interpolate*(*values*[1], *values*[2]), and so on, where *n* = *values*.length. In effect, this is a lightweight [linear scale](https://github.com/d3/d3-scale/blob/master/README.md#linear-scales). For example, to blend through red, green and blue:
+
+```js
+const interpolate = d3.piecewise(d3.interpolateRgb.gamma(2.2), ["red", "green", "blue"]);
+```
+
+If  *interpolate* is not specified, defaults to [d3.interpolate](#interpolate).

node_modules/d3-interpolate/dist/d3-interpolate.js

@@ -0,0 +1,590 @@
+// https://d3js.org/d3-interpolate/ v3.0.1 Copyright 2010-2021 Mike Bostock
+(function (global, factory) {
+typeof exports === 'object' && typeof module !== 'undefined' ? factory(exports, require('d3-color')) :
+typeof define === 'function' && define.amd ? define(['exports', 'd3-color'], factory) :
+(global = typeof globalThis !== 'undefined' ? globalThis : global || self, factory(global.d3 = global.d3 || {}, global.d3));
+}(this, (function (exports, d3Color) { 'use strict';
+
+function basis(t1, v0, v1, v2, v3) {
+  var t2 = t1 * t1, t3 = t2 * t1;
+  return ((1 - 3 * t1 + 3 * t2 - t3) * v0
+      + (4 - 6 * t2 + 3 * t3) * v1
+      + (1 + 3 * t1 + 3 * t2 - 3 * t3) * v2
+      + t3 * v3) / 6;
+}
+
+function basis$1(values) {
+  var n = values.length - 1;
+  return function(t) {
+    var i = t <= 0 ? (t = 0) : t >= 1 ? (t = 1, n - 1) : Math.floor(t * n),
+        v1 = values[i],
+        v2 = values[i + 1],
+        v0 = i > 0 ? values[i - 1] : 2 * v1 - v2,
+        v3 = i < n - 1 ? values[i + 2] : 2 * v2 - v1;
+    return basis((t - i / n) * n, v0, v1, v2, v3);
+  };
+}
+
+function basisClosed(values) {
+  var n = values.length;
+  return function(t) {
+    var i = Math.floor(((t %= 1) < 0 ? ++t : t) * n),
+        v0 = values[(i + n - 1) % n],
+        v1 = values[i % n],
+        v2 = values[(i + 1) % n],
+        v3 = values[(i + 2) % n];
+    return basis((t - i / n) * n, v0, v1, v2, v3);
+  };
+}
+
+var constant = x => () => x;
+
+function linear(a, d) {
+  return function(t) {
+    return a + t * d;
+  };
+}
+
+function exponential(a, b, y) {
+  return a = Math.pow(a, y), b = Math.pow(b, y) - a, y = 1 / y, function(t) {
+    return Math.pow(a + t * b, y);
+  };
+}
+
+function hue$1(a, b) {
+  var d = b - a;
+  return d ? linear(a, d > 180 || d < -180 ? d - 360 * Math.round(d / 360) : d) : constant(isNaN(a) ? b : a);
+}
+
+function gamma(y) {
+  return (y = +y) === 1 ? nogamma : function(a, b) {
+    return b - a ? exponential(a, b, y) : constant(isNaN(a) ? b : a);
+  };
+}
+
+function nogamma(a, b) {
+  var d = b - a;
+  return d ? linear(a, d) : constant(isNaN(a) ? b : a);
+}
+
+var rgb = (function rgbGamma(y) {
+  var color = gamma(y);
+
+  function rgb(start, end) {
+    var r = color((start = d3Color.rgb(start)).r, (end = d3Color.rgb(end)).r),
+        g = color(start.g, end.g),
+        b = color(start.b, end.b),
+        opacity = nogamma(start.opacity, end.opacity);
+    return function(t) {
+      start.r = r(t);
+      start.g = g(t);
+      start.b = b(t);
+      start.opacity = opacity(t);
+      return start + "";
+    };
+  }
+
+  rgb.gamma = rgbGamma;
+
+  return rgb;
+})(1);
+
+function rgbSpline(spline) {
+  return function(colors) {
+    var n = colors.length,
+        r = new Array(n),
+        g = new Array(n),
+        b = new Array(n),
+        i, color;
+    for (i = 0; i < n; ++i) {
+      color = d3Color.rgb(colors[i]);
+      r[i] = color.r || 0;
+      g[i] = color.g || 0;
+      b[i] = color.b || 0;
+    }
+    r = spline(r);
+    g = spline(g);
+    b = spline(b);
+    color.opacity = 1;
+    return function(t) {
+      color.r = r(t);
+      color.g = g(t);
+      color.b = b(t);
+      return color + "";
+    };
+  };
+}
+
+var rgbBasis = rgbSpline(basis$1);
+var rgbBasisClosed = rgbSpline(basisClosed);
+
+function numberArray(a, b) {
+  if (!b) b = [];
+  var n = a ? Math.min(b.length, a.length) : 0,
+      c = b.slice(),
+      i;
+  return function(t) {
+    for (i = 0; i < n; ++i) c[i] = a[i] * (1 - t) + b[i] * t;
+    return c;
+  };
+}
+
+function isNumberArray(x) {
+  return ArrayBuffer.isView(x) && !(x instanceof DataView);
+}
+
+function array(a, b) {
+  return (isNumberArray(b) ? numberArray : genericArray)(a, b);
+}
+
+function genericArray(a, b) {
+  var nb = b ? b.length : 0,
+      na = a ? Math.min(nb, a.length) : 0,
+      x = new Array(na),
+      c = new Array(nb),
+      i;
+
+  for (i = 0; i < na; ++i) x[i] = value(a[i], b[i]);
+  for (; i < nb; ++i) c[i] = b[i];
+
+  return function(t) {
+    for (i = 0; i < na; ++i) c[i] = x[i](t);
+    return c;
+  };
+}
+
+function date(a, b) {
+  var d = new Date;
+  return a = +a, b = +b, function(t) {
+    return d.setTime(a * (1 - t) + b * t), d;
+  };
+}
+
+function number(a, b) {
+  return a = +a, b = +b, function(t) {
+    return a * (1 - t) + b * t;
+  };
+}
+
+function object(a, b) {
+  var i = {},
+      c = {},
+      k;
+
+  if (a === null || typeof a !== "object") a = {};
+  if (b === null || typeof b !== "object") b = {};
+
+  for (k in b) {
+    if (k in a) {
+      i[k] = value(a[k], b[k]);
+    } else {
+      c[k] = b[k];
+    }
+  }
+
+  return function(t) {
+    for (k in i) c[k] = i[k](t);
+    return c;
+  };
+}
+
+var reA = /[-+]?(?:\d+\.?\d*|\.?\d+)(?:[eE][-+]?\d+)?/g,
+    reB = new RegExp(reA.source, "g");
+
+function zero(b) {
+  return function() {
+    return b;
+  };
+}
+
+function one(b) {
+  return function(t) {
+    return b(t) + "";
+  };
+}
+
+function string(a, b) {
+  var bi = reA.lastIndex = reB.lastIndex = 0, // scan index for next number in b
+      am, // current match in a
+      bm, // current match in b
+      bs, // string preceding current number in b, if any
+      i = -1, // index in s
+      s = [], // string constants and placeholders
+      q = []; // number interpolators
+
+  // Coerce inputs to strings.
+  a = a + "", b = b + "";
+
+  // Interpolate pairs of numbers in a & b.
+  while ((am = reA.exec(a))
+      && (bm = reB.exec(b))) {
+    if ((bs = bm.index) > bi) { // a string precedes the next number in b
+      bs = b.slice(bi, bs);
+      if (s[i]) s[i] += bs; // coalesce with previous string
+      else s[++i] = bs;
+    }
+    if ((am = am[0]) === (bm = bm[0])) { // numbers in a & b match
+      if (s[i]) s[i] += bm; // coalesce with previous string
+      else s[++i] = bm;
+    } else { // interpolate non-matching numbers
+      s[++i] = null;
+      q.push({i: i, x: number(am, bm)});
+    }
+    bi = reB.lastIndex;
+  }
+
+  // Add remains of b.
+  if (bi < b.length) {
+    bs = b.slice(bi);
+    if (s[i]) s[i] += bs; // coalesce with previous string
+    else s[++i] = bs;
+  }
+
+  // Special optimization for only a single match.
+  // Otherwise, interpolate each of the numbers and rejoin the string.
+  return s.length < 2 ? (q[0]
+      ? one(q[0].x)
+      : zero(b))
+      : (b = q.length, function(t) {
+          for (var i = 0, o; i < b; ++i) s[(o = q[i]).i] = o.x(t);
+          return s.join("");
+        });
+}
+
+function value(a, b) {
+  var t = typeof b, c;
+  return b == null || t === "boolean" ? constant(b)
+      : (t === "number" ? number
+      : t === "string" ? ((c = d3Color.color(b)) ? (b = c, rgb) : string)
+      : b instanceof d3Color.color ? rgb
+      : b instanceof Date ? date
+      : isNumberArray(b) ? numberArray
+      : Array.isArray(b) ? genericArray
+      : typeof b.valueOf !== "function" && typeof b.toString !== "function" || isNaN(b) ? object
+      : number)(a, b);
+}
+
+function discrete(range) {
+  var n = range.length;
+  return function(t) {
+    return range[Math.max(0, Math.min(n - 1, Math.floor(t * n)))];
+  };
+}
+
+function hue(a, b) {
+  var i = hue$1(+a, +b);
+  return function(t) {
+    var x = i(t);
+    return x - 360 * Math.floor(x / 360);
+  };
+}
+
+function round(a, b) {
+  return a = +a, b = +b, function(t) {
+    return Math.round(a * (1 - t) + b * t);
+  };
+}
+
+var degrees = 180 / Math.PI;
+
+var identity = {
+  translateX: 0,
+  translateY: 0,
+  rotate: 0,
+  skewX: 0,
+  scaleX: 1,
+  scaleY: 1
+};
+
+function decompose(a, b, c, d, e, f) {
+  var scaleX, scaleY, skewX;
+  if (scaleX = Math.sqrt(a * a + b * b)) a /= scaleX, b /= scaleX;
+  if (skewX = a * c + b * d) c -= a * skewX, d -= b * skewX;
+  if (scaleY = Math.sqrt(c * c + d * d)) c /= scaleY, d /= scaleY, skewX /= scaleY;
+  if (a * d < b * c) a = -a, b = -b, skewX = -skewX, scaleX = -scaleX;
+  return {
+    translateX: e,
+    translateY: f,
+    rotate: Math.atan2(b, a) * degrees,
+    skewX: Math.atan(skewX) * degrees,
+    scaleX: scaleX,
+    scaleY: scaleY
+  };
+}
+
+var svgNode;
+
+/* eslint-disable no-undef */
+function parseCss(value) {
+  const m = new (typeof DOMMatrix === "function" ? DOMMatrix : WebKitCSSMatrix)(value + "");
+  return m.isIdentity ? identity : decompose(m.a, m.b, m.c, m.d, m.e, m.f);
+}
+
+function parseSvg(value) {
+  if (value == null) return identity;
+  if (!svgNode) svgNode = document.createElementNS("http://www.w3.org/2000/svg", "g");
+  svgNode.setAttribute("transform", value);
+  if (!(value = svgNode.transform.baseVal.consolidate())) return identity;
+  value = value.matrix;
+  return decompose(value.a, value.b, value.c, value.d, value.e, value.f);
+}
+
+function interpolateTransform(parse, pxComma, pxParen, degParen) {
+
+  function pop(s) {
+    return s.length ? s.pop() + " " : "";
+  }
+
+  function translate(xa, ya, xb, yb, s, q) {
+    if (xa !== xb || ya !== yb) {
+      var i = s.push("translate(", null, pxComma, null, pxParen);
+      q.push({i: i - 4, x: number(xa, xb)}, {i: i - 2, x: number(ya, yb)});
+    } else if (xb || yb) {
+      s.push("translate(" + xb + pxComma + yb + pxParen);
+    }
+  }
+
+  function rotate(a, b, s, q) {
+    if (a !== b) {
+      if (a - b > 180) b += 360; else if (b - a > 180) a += 360; // shortest path
+      q.push({i: s.push(pop(s) + "rotate(", null, degParen) - 2, x: number(a, b)});
+    } else if (b) {
+      s.push(pop(s) + "rotate(" + b + degParen);
+    }
+  }
+
+  function skewX(a, b, s, q) {
+    if (a !== b) {
+      q.push({i: s.push(pop(s) + "skewX(", null, degParen) - 2, x: number(a, b)});
+    } else if (b) {
+      s.push(pop(s) + "skewX(" + b + degParen);
+    }
+  }
+
+  function scale(xa, ya, xb, yb, s, q) {
+    if (xa !== xb || ya !== yb) {
+      var i = s.push(pop(s) + "scale(", null, ",", null, ")");
+      q.push({i: i - 4, x: number(xa, xb)}, {i: i - 2, x: number(ya, yb)});
+    } else if (xb !== 1 || yb !== 1) {
+      s.push(pop(s) + "scale(" + xb + "," + yb + ")");
+    }
+  }
+
+  return function(a, b) {
+    var s = [], // string constants and placeholders
+        q = []; // number interpolators
+    a = parse(a), b = parse(b);
+    translate(a.translateX, a.translateY, b.translateX, b.translateY, s, q);
+    rotate(a.rotate, b.rotate, s, q);
+    skewX(a.skewX, b.skewX, s, q);
+    scale(a.scaleX, a.scaleY, b.scaleX, b.scaleY, s, q);
+    a = b = null; // gc
+    return function(t) {
+      var i = -1, n = q.length, o;
+      while (++i < n) s[(o = q[i]).i] = o.x(t);
+      return s.join("");
+    };
+  };
+}
+
+var interpolateTransformCss = interpolateTransform(parseCss, "px, ", "px)", "deg)");
+var interpolateTransformSvg = interpolateTransform(parseSvg, ", ", ")", ")");
+
+var epsilon2 = 1e-12;
+
+function cosh(x) {
+  return ((x = Math.exp(x)) + 1 / x) / 2;
+}
+
+function sinh(x) {
+  return ((x = Math.exp(x)) - 1 / x) / 2;
+}
+
+function tanh(x) {
+  return ((x = Math.exp(2 * x)) - 1) / (x + 1);
+}
+
+var zoom = (function zoomRho(rho, rho2, rho4) {
+
+  // p0 = [ux0, uy0, w0]
+  // p1 = [ux1, uy1, w1]
+  function zoom(p0, p1) {
+    var ux0 = p0[0], uy0 = p0[1], w0 = p0[2],
+        ux1 = p1[0], uy1 = p1[1], w1 = p1[2],
+        dx = ux1 - ux0,
+        dy = uy1 - uy0,
+        d2 = dx * dx + dy * dy,
+        i,
+        S;
+
+    // Special case for u0 ≅ u1.
+    if (d2 < epsilon2) {
+      S = Math.log(w1 / w0) / rho;
+      i = function(t) {
+        return [
+          ux0 + t * dx,
+          uy0 + t * dy,
+          w0 * Math.exp(rho * t * S)
+        ];
+      };
+    }
+
+    // General case.
+    else {
+      var d1 = Math.sqrt(d2),
+          b0 = (w1 * w1 - w0 * w0 + rho4 * d2) / (2 * w0 * rho2 * d1),
+          b1 = (w1 * w1 - w0 * w0 - rho4 * d2) / (2 * w1 * rho2 * d1),
+          r0 = Math.log(Math.sqrt(b0 * b0 + 1) - b0),
+          r1 = Math.log(Math.sqrt(b1 * b1 + 1) - b1);
+      S = (r1 - r0) / rho;
+      i = function(t) {
+        var s = t * S,
+            coshr0 = cosh(r0),
+            u = w0 / (rho2 * d1) * (coshr0 * tanh(rho * s + r0) - sinh(r0));
+        return [
+          ux0 + u * dx,
+          uy0 + u * dy,
+          w0 * coshr0 / cosh(rho * s + r0)
+        ];
+      };
+    }
+
+    i.duration = S * 1000 * rho / Math.SQRT2;
+
+    return i;
+  }
+
+  zoom.rho = function(_) {
+    var _1 = Math.max(1e-3, +_), _2 = _1 * _1, _4 = _2 * _2;
+    return zoomRho(_1, _2, _4);
+  };
+
+  return zoom;
+})(Math.SQRT2, 2, 4);
+
+function hsl(hue) {
+  return function(start, end) {
+    var h = hue((start = d3Color.hsl(start)).h, (end = d3Color.hsl(end)).h),
+        s = nogamma(start.s, end.s),
+        l = nogamma(start.l, end.l),
+        opacity = nogamma(start.opacity, end.opacity);
+    return function(t) {
+      start.h = h(t);
+      start.s = s(t);
+      start.l = l(t);
+      start.opacity = opacity(t);
+      return start + "";
+    };
+  }
+}
+
+var hsl$1 = hsl(hue$1);
+var hslLong = hsl(nogamma);
+
+function lab(start, end) {
+  var l = nogamma((start = d3Color.lab(start)).l, (end = d3Color.lab(end)).l),
+      a = nogamma(start.a, end.a),
+      b = nogamma(start.b, end.b),
+      opacity = nogamma(start.opacity, end.opacity);
+  return function(t) {
+    start.l = l(t);
+    start.a = a(t);
+    start.b = b(t);
+    start.opacity = opacity(t);
+    return start + "";
+  };
+}
+
+function hcl(hue) {
+  return function(start, end) {
+    var h = hue((start = d3Color.hcl(start)).h, (end = d3Color.hcl(end)).h),
+        c = nogamma(start.c, end.c),
+        l = nogamma(start.l, end.l),
+        opacity = nogamma(start.opacity, end.opacity);
+    return function(t) {
+      start.h = h(t);
+      start.c = c(t);
+      start.l = l(t);
+      start.opacity = opacity(t);
+      return start + "";
+    };
+  }
+}
+
+var hcl$1 = hcl(hue$1);
+var hclLong = hcl(nogamma);
+
+function cubehelix(hue) {
+  return (function cubehelixGamma(y) {
+    y = +y;
+
+    function cubehelix(start, end) {
+      var h = hue((start = d3Color.cubehelix(start)).h, (end = d3Color.cubehelix(end)).h),
+          s = nogamma(start.s, end.s),
+          l = nogamma(start.l, end.l),
+          opacity = nogamma(start.opacity, end.opacity);
+      return function(t) {
+        start.h = h(t);
+        start.s = s(t);
+        start.l = l(Math.pow(t, y));
+        start.opacity = opacity(t);
+        return start + "";
+      };
+    }
+
+    cubehelix.gamma = cubehelixGamma;
+
+    return cubehelix;
+  })(1);
+}
+
+var cubehelix$1 = cubehelix(hue$1);
+var cubehelixLong = cubehelix(nogamma);
+
+function piecewise(interpolate, values) {
+  if (values === undefined) values = interpolate, interpolate = value;
+  var i = 0, n = values.length - 1, v = values[0], I = new Array(n < 0 ? 0 : n);
+  while (i < n) I[i] = interpolate(v, v = values[++i]);
+  return function(t) {
+    var i = Math.max(0, Math.min(n - 1, Math.floor(t *= n)));
+    return I[i](t - i);
+  };
+}
+
+function quantize(interpolator, n) {
+  var samples = new Array(n);
+  for (var i = 0; i < n; ++i) samples[i] = interpolator(i / (n - 1));
+  return samples;
+}
+
+exports.interpolate = value;
+exports.interpolateArray = array;
+exports.interpolateBasis = basis$1;
+exports.interpolateBasisClosed = basisClosed;
+exports.interpolateCubehelix = cubehelix$1;
+exports.interpolateCubehelixLong = cubehelixLong;
+exports.interpolateDate = date;
+exports.interpolateDiscrete = discrete;
+exports.interpolateHcl = hcl$1;
+exports.interpolateHclLong = hclLong;
+exports.interpolateHsl = hsl$1;
+exports.interpolateHslLong = hslLong;
+exports.interpolateHue = hue;
+exports.interpolateLab = lab;
+exports.interpolateNumber = number;
+exports.interpolateNumberArray = numberArray;
+exports.interpolateObject = object;
+exports.interpolateRgb = rgb;
+exports.interpolateRgbBasis = rgbBasis;
+exports.interpolateRgbBasisClosed = rgbBasisClosed;
+exports.interpolateRound = round;
+exports.interpolateString = string;
+exports.interpolateTransformCss = interpolateTransformCss;
+exports.interpolateTransformSvg = interpolateTransformSvg;
+exports.interpolateZoom = zoom;
+exports.piecewise = piecewise;
+exports.quantize = quantize;
+
+Object.defineProperty(exports, '__esModule', { value: true });
+
+})));

node_modules/d3-interpolate/package.json

@@ -0,0 +1,53 @@
+{
+  "name": "d3-interpolate",
+  "version": "3.0.1",
+  "description": "Interpolate numbers, colors, strings, arrays, objects, whatever!",
+  "homepage": "https://d3js.org/d3-interpolate/",
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/d3/d3-interpolate.git"
+  },
+  "keywords": [
+    "d3",
+    "d3-module",
+    "interpolate",
+    "interpolation",
+    "color"
+  ],
+  "license": "ISC",
+  "author": {
+    "name": "Mike Bostock",
+    "url": "http://bost.ocks.org/mike"
+  },
+  "type": "module",
+  "files": [
+    "dist/**/*.js",
+    "src/**/*.js"
+  ],
+  "module": "src/index.js",
+  "main": "src/index.js",
+  "jsdelivr": "dist/d3-interpolate.min.js",
+  "unpkg": "dist/d3-interpolate.min.js",
+  "exports": {
+    "umd": "./dist/d3-interpolate.min.js",
+    "default": "./src/index.js"
+  },
+  "sideEffects": false,
+  "dependencies": {
+    "d3-color": "1 - 3"
+  },
+  "devDependencies": {
+    "eslint": "7",
+    "mocha": "8",
+    "rollup": "2",
+    "rollup-plugin-terser": "7"
+  },
+  "scripts": {
+    "test": "mocha 'test/**/*-test.js' && eslint src test",
+    "prepublishOnly": "rm -rf dist && yarn test && rollup -c",
+    "postpublish": "git push && git push --tags && cd ../d3.github.com && git pull && cp ../${npm_package_name}/dist/${npm_package_name}.js ${npm_package_name}.v${npm_package_version%%.*}.js && cp ../${npm_package_name}/dist/${npm_package_name}.min.js ${npm_package_name}.v${npm_package_version%%.*}.min.js && git add ${npm_package_name}.v${npm_package_version%%.*}.js ${npm_package_name}.v${npm_package_version%%.*}.min.js && git commit -m \"${npm_package_name} ${npm_package_version}\" && git push && cd -"
+  },
+  "engines": {
+    "node": ">=12"
+  }
+}

node_modules/d3-interpolate/src/array.js

@@ -0,0 +1,22 @@
+import value from "./value.js";
+import numberArray, {isNumberArray} from "./numberArray.js";
+
+export default function(a, b) {
+  return (isNumberArray(b) ? numberArray : genericArray)(a, b);
+}
+
+export function genericArray(a, b) {
+  var nb = b ? b.length : 0,
+      na = a ? Math.min(nb, a.length) : 0,
+      x = new Array(na),
+      c = new Array(nb),
+      i;
+
+  for (i = 0; i < na; ++i) x[i] = value(a[i], b[i]);
+  for (; i < nb; ++i) c[i] = b[i];
+
+  return function(t) {
+    for (i = 0; i < na; ++i) c[i] = x[i](t);
+    return c;
+  };
+}

node_modules/d3-interpolate/src/basis.js

@@ -0,0 +1,19 @@
+export function basis(t1, v0, v1, v2, v3) {
+  var t2 = t1 * t1, t3 = t2 * t1;
+  return ((1 - 3 * t1 + 3 * t2 - t3) * v0
+      + (4 - 6 * t2 + 3 * t3) * v1
+      + (1 + 3 * t1 + 3 * t2 - 3 * t3) * v2
+      + t3 * v3) / 6;
+}
+
+export default function(values) {
+  var n = values.length - 1;
+  return function(t) {
+    var i = t <= 0 ? (t = 0) : t >= 1 ? (t = 1, n - 1) : Math.floor(t * n),
+        v1 = values[i],
+        v2 = values[i + 1],
+        v0 = i > 0 ? values[i - 1] : 2 * v1 - v2,
+        v3 = i < n - 1 ? values[i + 2] : 2 * v2 - v1;
+    return basis((t - i / n) * n, v0, v1, v2, v3);
+  };
+}

node_modules/d3-interpolate/src/basisClosed.js

@@ -0,0 +1,13 @@
+import {basis} from "./basis.js";
+
+export default function(values) {
+  var n = values.length;
+  return function(t) {
+    var i = Math.floor(((t %= 1) < 0 ? ++t : t) * n),
+        v0 = values[(i + n - 1) % n],
+        v1 = values[i % n],
+        v2 = values[(i + 1) % n],
+        v3 = values[(i + 2) % n];
+    return basis((t - i / n) * n, v0, v1, v2, v3);
+  };
+}

node_modules/d3-interpolate/src/color.js

@@ -0,0 +1,29 @@
+import constant from "./constant.js";
+
+function linear(a, d) {
+  return function(t) {
+    return a + t * d;
+  };
+}
+
+function exponential(a, b, y) {
+  return a = Math.pow(a, y), b = Math.pow(b, y) - a, y = 1 / y, function(t) {
+    return Math.pow(a + t * b, y);
+  };
+}
+
+export function hue(a, b) {
+  var d = b - a;
+  return d ? linear(a, d > 180 || d < -180 ? d - 360 * Math.round(d / 360) : d) : constant(isNaN(a) ? b : a);
+}
+
+export function gamma(y) {
+  return (y = +y) === 1 ? nogamma : function(a, b) {
+    return b - a ? exponential(a, b, y) : constant(isNaN(a) ? b : a);
+  };
+}
+
+export default function nogamma(a, b) {
+  var d = b - a;
+  return d ? linear(a, d) : constant(isNaN(a) ? b : a);
+}

node_modules/d3-interpolate/src/constant.js

@@ -0,0 +1 @@
+export default x => () => x;

node_modules/d3-interpolate/src/cubehelix.js

@@ -0,0 +1,29 @@
+import {cubehelix as colorCubehelix} from "d3-color";
+import color, {hue} from "./color.js";
+
+function cubehelix(hue) {
+  return (function cubehelixGamma(y) {
+    y = +y;
+
+    function cubehelix(start, end) {
+      var h = hue((start = colorCubehelix(start)).h, (end = colorCubehelix(end)).h),
+          s = color(start.s, end.s),
+          l = color(start.l, end.l),
+          opacity = color(start.opacity, end.opacity);
+      return function(t) {
+        start.h = h(t);
+        start.s = s(t);
+        start.l = l(Math.pow(t, y));
+        start.opacity = opacity(t);
+        return start + "";
+      };
+    }
+
+    cubehelix.gamma = cubehelixGamma;
+
+    return cubehelix;
+  })(1);
+}
+
+export default cubehelix(hue);
+export var cubehelixLong = cubehelix(color);

node_modules/d3-interpolate/src/date.js

@@ -0,0 +1,6 @@
+export default function(a, b) {
+  var d = new Date;
+  return a = +a, b = +b, function(t) {
+    return d.setTime(a * (1 - t) + b * t), d;
+  };
+}

node_modules/d3-interpolate/src/discrete.js

@@ -0,0 +1,6 @@
+export default function(range) {
+  var n = range.length;
+  return function(t) {
+    return range[Math.max(0, Math.min(n - 1, Math.floor(t * n)))];
+  };
+}

node_modules/d3-interpolate/src/hcl.js

@@ -0,0 +1,21 @@
+import {hcl as colorHcl} from "d3-color";
+import color, {hue} from "./color.js";
+
+function hcl(hue) {
+  return function(start, end) {
+    var h = hue((start = colorHcl(start)).h, (end = colorHcl(end)).h),
+        c = color(start.c, end.c),
+        l = color(start.l, end.l),
+        opacity = color(start.opacity, end.opacity);
+    return function(t) {
+      start.h = h(t);
+      start.c = c(t);
+      start.l = l(t);
+      start.opacity = opacity(t);
+      return start + "";
+    };
+  }
+}
+
+export default hcl(hue);
+export var hclLong = hcl(color);

node_modules/d3-interpolate/src/hsl.js

@@ -0,0 +1,21 @@
+import {hsl as colorHsl} from "d3-color";
+import color, {hue} from "./color.js";
+
+function hsl(hue) {
+  return function(start, end) {
+    var h = hue((start = colorHsl(start)).h, (end = colorHsl(end)).h),
+        s = color(start.s, end.s),
+        l = color(start.l, end.l),
+        opacity = color(start.opacity, end.opacity);
+    return function(t) {
+      start.h = h(t);
+      start.s = s(t);
+      start.l = l(t);
+      start.opacity = opacity(t);
+      return start + "";
+    };
+  }
+}
+
+export default hsl(hue);
+export var hslLong = hsl(color);

node_modules/d3-interpolate/src/hue.js

@@ -0,0 +1,9 @@
+import {hue} from "./color.js";
+
+export default function(a, b) {
+  var i = hue(+a, +b);
+  return function(t) {
+    var x = i(t);
+    return x - 360 * Math.floor(x / 360);
+  };
+}

node_modules/d3-interpolate/src/index.js

@@ -0,0 +1,21 @@
+export {default as interpolate} from "./value.js";
+export {default as interpolateArray} from "./array.js";
+export {default as interpolateBasis} from "./basis.js";
+export {default as interpolateBasisClosed} from "./basisClosed.js";
+export {default as interpolateDate} from "./date.js";
+export {default as interpolateDiscrete} from "./discrete.js";
+export {default as interpolateHue} from "./hue.js";
+export {default as interpolateNumber} from "./number.js";
+export {default as interpolateNumberArray} from "./numberArray.js";
+export {default as interpolateObject} from "./object.js";
+export {default as interpolateRound} from "./round.js";
+export {default as interpolateString} from "./string.js";
+export {interpolateTransformCss, interpolateTransformSvg} from "./transform/index.js";
+export {default as interpolateZoom} from "./zoom.js";
+export {default as interpolateRgb, rgbBasis as interpolateRgbBasis, rgbBasisClosed as interpolateRgbBasisClosed} from "./rgb.js";
+export {default as interpolateHsl, hslLong as interpolateHslLong} from "./hsl.js";
+export {default as interpolateLab} from "./lab.js";
+export {default as interpolateHcl, hclLong as interpolateHclLong} from "./hcl.js";
+export {default as interpolateCubehelix, cubehelixLong as interpolateCubehelixLong} from "./cubehelix.js";
+export {default as piecewise} from "./piecewise.js";
+export {default as quantize} from "./quantize.js";

node_modules/d3-interpolate/src/lab.js

@@ -0,0 +1,16 @@
+import {lab as colorLab} from "d3-color";
+import color from "./color.js";
+
+export default function lab(start, end) {
+  var l = color((start = colorLab(start)).l, (end = colorLab(end)).l),
+      a = color(start.a, end.a),
+      b = color(start.b, end.b),
+      opacity = color(start.opacity, end.opacity);
+  return function(t) {
+    start.l = l(t);
+    start.a = a(t);
+    start.b = b(t);
+    start.opacity = opacity(t);
+    return start + "";
+  };
+}

node_modules/d3-interpolate/src/number.js

@@ -0,0 +1,5 @@
+export default function(a, b) {
+  return a = +a, b = +b, function(t) {
+    return a * (1 - t) + b * t;
+  };
+}

node_modules/d3-interpolate/src/numberArray.js

@@ -0,0 +1,14 @@
+export default function(a, b) {
+  if (!b) b = [];
+  var n = a ? Math.min(b.length, a.length) : 0,
+      c = b.slice(),
+      i;
+  return function(t) {
+    for (i = 0; i < n; ++i) c[i] = a[i] * (1 - t) + b[i] * t;
+    return c;
+  };
+}
+
+export function isNumberArray(x) {
+  return ArrayBuffer.isView(x) && !(x instanceof DataView);
+}

node_modules/d3-interpolate/src/object.js

@@ -0,0 +1,23 @@
+import value from "./value.js";
+
+export default function(a, b) {
+  var i = {},
+      c = {},
+      k;
+
+  if (a === null || typeof a !== "object") a = {};
+  if (b === null || typeof b !== "object") b = {};
+
+  for (k in b) {
+    if (k in a) {
+      i[k] = value(a[k], b[k]);
+    } else {
+      c[k] = b[k];
+    }
+  }
+
+  return function(t) {
+    for (k in i) c[k] = i[k](t);
+    return c;
+  };
+}

node_modules/d3-interpolate/src/piecewise.js

@@ -0,0 +1,11 @@
+import {default as value} from "./value.js";
+
+export default function piecewise(interpolate, values) {
+  if (values === undefined) values = interpolate, interpolate = value;
+  var i = 0, n = values.length - 1, v = values[0], I = new Array(n < 0 ? 0 : n);
+  while (i < n) I[i] = interpolate(v, v = values[++i]);
+  return function(t) {
+    var i = Math.max(0, Math.min(n - 1, Math.floor(t *= n)));
+    return I[i](t - i);
+  };
+}

node_modules/d3-interpolate/src/quantize.js

@@ -0,0 +1,5 @@
+export default function(interpolator, n) {
+  var samples = new Array(n);
+  for (var i = 0; i < n; ++i) samples[i] = interpolator(i / (n - 1));
+  return samples;
+}

node_modules/d3-interpolate/src/rgb.js

@@ -0,0 +1,55 @@
+import {rgb as colorRgb} from "d3-color";
+import basis from "./basis.js";
+import basisClosed from "./basisClosed.js";
+import nogamma, {gamma} from "./color.js";
+
+export default (function rgbGamma(y) {
+  var color = gamma(y);
+
+  function rgb(start, end) {
+    var r = color((start = colorRgb(start)).r, (end = colorRgb(end)).r),
+        g = color(start.g, end.g),
+        b = color(start.b, end.b),
+        opacity = nogamma(start.opacity, end.opacity);
+    return function(t) {
+      start.r = r(t);
+      start.g = g(t);
+      start.b = b(t);
+      start.opacity = opacity(t);
+      return start + "";
+    };
+  }
+
+  rgb.gamma = rgbGamma;
+
+  return rgb;
+})(1);
+
+function rgbSpline(spline) {
+  return function(colors) {
+    var n = colors.length,
+        r = new Array(n),
+        g = new Array(n),
+        b = new Array(n),
+        i, color;
+    for (i = 0; i < n; ++i) {
+      color = colorRgb(colors[i]);
+      r[i] = color.r || 0;
+      g[i] = color.g || 0;
+      b[i] = color.b || 0;
+    }
+    r = spline(r);
+    g = spline(g);
+    b = spline(b);
+    color.opacity = 1;
+    return function(t) {
+      color.r = r(t);
+      color.g = g(t);
+      color.b = b(t);
+      return color + "";
+    };
+  };
+}
+
+export var rgbBasis = rgbSpline(basis);
+export var rgbBasisClosed = rgbSpline(basisClosed);

node_modules/d3-interpolate/src/round.js

@@ -0,0 +1,5 @@
+export default function(a, b) {
+  return a = +a, b = +b, function(t) {
+    return Math.round(a * (1 - t) + b * t);
+  };
+}

node_modules/d3-interpolate/src/string.js

@@ -0,0 +1,64 @@
+import number from "./number.js";
+
+var reA = /[-+]?(?:\d+\.?\d*|\.?\d+)(?:[eE][-+]?\d+)?/g,
+    reB = new RegExp(reA.source, "g");
+
+function zero(b) {
+  return function() {
+    return b;
+  };
+}
+
+function one(b) {
+  return function(t) {
+    return b(t) + "";
+  };
+}
+
+export default function(a, b) {
+  var bi = reA.lastIndex = reB.lastIndex = 0, // scan index for next number in b
+      am, // current match in a
+      bm, // current match in b
+      bs, // string preceding current number in b, if any
+      i = -1, // index in s
+      s = [], // string constants and placeholders
+      q = []; // number interpolators
+
+  // Coerce inputs to strings.
+  a = a + "", b = b + "";
+
+  // Interpolate pairs of numbers in a & b.
+  while ((am = reA.exec(a))
+      && (bm = reB.exec(b))) {
+    if ((bs = bm.index) > bi) { // a string precedes the next number in b
+      bs = b.slice(bi, bs);
+      if (s[i]) s[i] += bs; // coalesce with previous string
+      else s[++i] = bs;
+    }
+    if ((am = am[0]) === (bm = bm[0])) { // numbers in a & b match
+      if (s[i]) s[i] += bm; // coalesce with previous string
+      else s[++i] = bm;
+    } else { // interpolate non-matching numbers
+      s[++i] = null;
+      q.push({i: i, x: number(am, bm)});
+    }
+    bi = reB.lastIndex;
+  }
+
+  // Add remains of b.
+  if (bi < b.length) {
+    bs = b.slice(bi);
+    if (s[i]) s[i] += bs; // coalesce with previous string
+    else s[++i] = bs;
+  }
+
+  // Special optimization for only a single match.
+  // Otherwise, interpolate each of the numbers and rejoin the string.
+  return s.length < 2 ? (q[0]
+      ? one(q[0].x)
+      : zero(b))
+      : (b = q.length, function(t) {
+          for (var i = 0, o; i < b; ++i) s[(o = q[i]).i] = o.x(t);
+          return s.join("");
+        });
+}

node_modules/d3-interpolate/src/transform/decompose.js

@@ -0,0 +1,26 @@
+var degrees = 180 / Math.PI;
+
+export var identity = {
+  translateX: 0,
+  translateY: 0,
+  rotate: 0,
+  skewX: 0,
+  scaleX: 1,
+  scaleY: 1
+};
+
+export default function(a, b, c, d, e, f) {
+  var scaleX, scaleY, skewX;
+  if (scaleX = Math.sqrt(a * a + b * b)) a /= scaleX, b /= scaleX;
+  if (skewX = a * c + b * d) c -= a * skewX, d -= b * skewX;
+  if (scaleY = Math.sqrt(c * c + d * d)) c /= scaleY, d /= scaleY, skewX /= scaleY;
+  if (a * d < b * c) a = -a, b = -b, skewX = -skewX, scaleX = -scaleX;
+  return {
+    translateX: e,
+    translateY: f,
+    rotate: Math.atan2(b, a) * degrees,
+    skewX: Math.atan(skewX) * degrees,
+    scaleX: scaleX,
+    scaleY: scaleY
+  };
+}

node_modules/d3-interpolate/src/transform/index.js

@@ -0,0 +1,63 @@
+import number from "../number.js";
+import {parseCss, parseSvg} from "./parse.js";
+
+function interpolateTransform(parse, pxComma, pxParen, degParen) {
+
+  function pop(s) {
+    return s.length ? s.pop() + " " : "";
+  }
+
+  function translate(xa, ya, xb, yb, s, q) {
+    if (xa !== xb || ya !== yb) {
+      var i = s.push("translate(", null, pxComma, null, pxParen);
+      q.push({i: i - 4, x: number(xa, xb)}, {i: i - 2, x: number(ya, yb)});
+    } else if (xb || yb) {
+      s.push("translate(" + xb + pxComma + yb + pxParen);
+    }
+  }
+
+  function rotate(a, b, s, q) {
+    if (a !== b) {
+      if (a - b > 180) b += 360; else if (b - a > 180) a += 360; // shortest path
+      q.push({i: s.push(pop(s) + "rotate(", null, degParen) - 2, x: number(a, b)});
+    } else if (b) {
+      s.push(pop(s) + "rotate(" + b + degParen);
+    }
+  }
+
+  function skewX(a, b, s, q) {
+    if (a !== b) {
+      q.push({i: s.push(pop(s) + "skewX(", null, degParen) - 2, x: number(a, b)});
+    } else if (b) {
+      s.push(pop(s) + "skewX(" + b + degParen);
+    }
+  }
+
+  function scale(xa, ya, xb, yb, s, q) {
+    if (xa !== xb || ya !== yb) {
+      var i = s.push(pop(s) + "scale(", null, ",", null, ")");
+      q.push({i: i - 4, x: number(xa, xb)}, {i: i - 2, x: number(ya, yb)});
+    } else if (xb !== 1 || yb !== 1) {
+      s.push(pop(s) + "scale(" + xb + "," + yb + ")");
+    }
+  }
+
+  return function(a, b) {
+    var s = [], // string constants and placeholders
+        q = []; // number interpolators
+    a = parse(a), b = parse(b);
+    translate(a.translateX, a.translateY, b.translateX, b.translateY, s, q);
+    rotate(a.rotate, b.rotate, s, q);
+    skewX(a.skewX, b.skewX, s, q);
+    scale(a.scaleX, a.scaleY, b.scaleX, b.scaleY, s, q);
+    a = b = null; // gc
+    return function(t) {
+      var i = -1, n = q.length, o;
+      while (++i < n) s[(o = q[i]).i] = o.x(t);
+      return s.join("");
+    };
+  };
+}
+
+export var interpolateTransformCss = interpolateTransform(parseCss, "px, ", "px)", "deg)");
+export var interpolateTransformSvg = interpolateTransform(parseSvg, ", ", ")", ")");

node_modules/d3-interpolate/src/transform/parse.js

@@ -0,0 +1,18 @@
+import decompose, {identity} from "./decompose.js";
+
+var svgNode;
+
+/* eslint-disable no-undef */
+export function parseCss(value) {
+  const m = new (typeof DOMMatrix === "function" ? DOMMatrix : WebKitCSSMatrix)(value + "");
+  return m.isIdentity ? identity : decompose(m.a, m.b, m.c, m.d, m.e, m.f);
+}
+
+export function parseSvg(value) {
+  if (value == null) return identity;
+  if (!svgNode) svgNode = document.createElementNS("http://www.w3.org/2000/svg", "g");
+  svgNode.setAttribute("transform", value);
+  if (!(value = svgNode.transform.baseVal.consolidate())) return identity;
+  value = value.matrix;
+  return decompose(value.a, value.b, value.c, value.d, value.e, value.f);
+}

node_modules/d3-interpolate/src/value.js

@@ -0,0 +1,22 @@
+import {color} from "d3-color";
+import rgb from "./rgb.js";
+import {genericArray} from "./array.js";
+import date from "./date.js";
+import number from "./number.js";
+import object from "./object.js";
+import string from "./string.js";
+import constant from "./constant.js";
+import numberArray, {isNumberArray} from "./numberArray.js";
+
+export default function(a, b) {
+  var t = typeof b, c;
+  return b == null || t === "boolean" ? constant(b)
+      : (t === "number" ? number
+      : t === "string" ? ((c = color(b)) ? (b = c, rgb) : string)
+      : b instanceof color ? rgb
+      : b instanceof Date ? date
+      : isNumberArray(b) ? numberArray
+      : Array.isArray(b) ? genericArray
+      : typeof b.valueOf !== "function" && typeof b.toString !== "function" || isNaN(b) ? object
+      : number)(a, b);
+}

node_modules/d3-interpolate/src/zoom.js

@@ -0,0 +1,71 @@
+var epsilon2 = 1e-12;
+
+function cosh(x) {
+  return ((x = Math.exp(x)) + 1 / x) / 2;
+}
+
+function sinh(x) {
+  return ((x = Math.exp(x)) - 1 / x) / 2;
+}
+
+function tanh(x) {
+  return ((x = Math.exp(2 * x)) - 1) / (x + 1);
+}
+
+export default (function zoomRho(rho, rho2, rho4) {
+
+  // p0 = [ux0, uy0, w0]
+  // p1 = [ux1, uy1, w1]
+  function zoom(p0, p1) {
+    var ux0 = p0[0], uy0 = p0[1], w0 = p0[2],
+        ux1 = p1[0], uy1 = p1[1], w1 = p1[2],
+        dx = ux1 - ux0,
+        dy = uy1 - uy0,
+        d2 = dx * dx + dy * dy,
+        i,
+        S;
+
+    // Special case for u0 ≅ u1.
+    if (d2 < epsilon2) {
+      S = Math.log(w1 / w0) / rho;
+      i = function(t) {
+        return [
+          ux0 + t * dx,
+          uy0 + t * dy,
+          w0 * Math.exp(rho * t * S)
+        ];
+      }
+    }
+
+    // General case.
+    else {
+      var d1 = Math.sqrt(d2),
+          b0 = (w1 * w1 - w0 * w0 + rho4 * d2) / (2 * w0 * rho2 * d1),
+          b1 = (w1 * w1 - w0 * w0 - rho4 * d2) / (2 * w1 * rho2 * d1),
+          r0 = Math.log(Math.sqrt(b0 * b0 + 1) - b0),
+          r1 = Math.log(Math.sqrt(b1 * b1 + 1) - b1);
+      S = (r1 - r0) / rho;
+      i = function(t) {
+        var s = t * S,
+            coshr0 = cosh(r0),
+            u = w0 / (rho2 * d1) * (coshr0 * tanh(rho * s + r0) - sinh(r0));
+        return [
+          ux0 + u * dx,
+          uy0 + u * dy,
+          w0 * coshr0 / cosh(rho * s + r0)
+        ];
+      }
+    }
+
+    i.duration = S * 1000 * rho / Math.SQRT2;
+
+    return i;
+  }
+
+  zoom.rho = function(_) {
+    var _1 = Math.max(1e-3, +_), _2 = _1 * _1, _4 = _2 * _2;
+    return zoomRho(_1, _2, _4);
+  };
+
+  return zoom;
+})(Math.SQRT2, 2, 4);