Bar graph added.

node_modules/d3-geo/src/adder.js

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+// Adds floating point numbers with twice the normal precision.
+// Reference: J. R. Shewchuk, Adaptive Precision Floating-Point Arithmetic and
+// Fast Robust Geometric Predicates, Discrete & Computational Geometry 18(3)
+// 305–363 (1997).
+// Code adapted from GeographicLib by Charles F. F. Karney,
+// http://geographiclib.sourceforge.net/
+
+export default function() {
+  return new Adder;
+}
+
+function Adder() {
+  this.reset();
+}
+
+Adder.prototype = {
+  constructor: Adder,
+  reset: function() {
+    this.s = // rounded value
+    this.t = 0; // exact error
+  },
+  add: function(y) {
+    add(temp, y, this.t);
+    add(this, temp.s, this.s);
+    if (this.s) this.t += temp.t;
+    else this.s = temp.t;
+  },
+  valueOf: function() {
+    return this.s;
+  }
+};
+
+var temp = new Adder;
+
+function add(adder, a, b) {
+  var x = adder.s = a + b,
+      bv = x - a,
+      av = x - bv;
+  adder.t = (a - av) + (b - bv);
+}