Initial commit

node_modules/d3-array/src/histogram.js

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+import {slice} from "./array";
+import bisect from "./bisect";
+import constant from "./constant";
+import extent from "./extent";
+import identity from "./identity";
+import range from "./range";
+import {tickStep} from "./ticks";
+import sturges from "./threshold/sturges";
+
+export default function() {
+  var value = identity,
+      domain = extent,
+      threshold = sturges;
+
+  function histogram(data) {
+    var i,
+        n = data.length,
+        x,
+        values = new Array(n);
+
+    for (i = 0; i < n; ++i) {
+      values[i] = value(data[i], i, data);
+    }
+
+    var xz = domain(values),
+        x0 = xz[0],
+        x1 = xz[1],
+        tz = threshold(values, x0, x1);
+
+    // Convert number of thresholds into uniform thresholds.
+    if (!Array.isArray(tz)) {
+      tz = tickStep(x0, x1, tz);
+      tz = range(Math.ceil(x0 / tz) * tz, x1, tz); // exclusive
+    }
+
+    // Remove any thresholds outside the domain.
+    var m = tz.length;
+    while (tz[0] <= x0) tz.shift(), --m;
+    while (tz[m - 1] > x1) tz.pop(), --m;
+
+    var bins = new Array(m + 1),
+        bin;
+
+    // Initialize bins.
+    for (i = 0; i <= m; ++i) {
+      bin = bins[i] = [];
+      bin.x0 = i > 0 ? tz[i - 1] : x0;
+      bin.x1 = i < m ? tz[i] : x1;
+    }
+
+    // Assign data to bins by value, ignoring any outside the domain.
+    for (i = 0; i < n; ++i) {
+      x = values[i];
+      if (x0 <= x && x <= x1) {
+        bins[bisect(tz, x, 0, m)].push(data[i]);
+      }
+    }
+
+    return bins;
+  }
+
+  histogram.value = function(_) {
+    return arguments.length ? (value = typeof _ === "function" ? _ : constant(_), histogram) : value;
+  };
+
+  histogram.domain = function(_) {
+    return arguments.length ? (domain = typeof _ === "function" ? _ : constant([_[0], _[1]]), histogram) : domain;
+  };
+
+  histogram.thresholds = function(_) {
+    return arguments.length ? (threshold = typeof _ === "function" ? _ : Array.isArray(_) ? constant(slice.call(_)) : constant(_), histogram) : threshold;
+  };
+
+  return histogram;
+}