Update wmts-hidpi, add nicer-api-docs

nicer-api-docs/closure-library/closure/goog/math/interpolator/pchip1.js

@@ -0,0 +1,81 @@
+// Copyright 2012 The Closure Library Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS-IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+/**
+ * @fileoverview A one dimensional monotone cubic spline interpolator.
+ *
+ * See http://en.wikipedia.org/wiki/Monotone_cubic_interpolation.
+ *
+ */
+
+goog.provide('goog.math.interpolator.Pchip1');
+
+goog.require('goog.math');
+goog.require('goog.math.interpolator.Spline1');
+
+
+
+/**
+ * A one dimensional monotone cubic spline interpolator.
+ * @extends {goog.math.interpolator.Spline1}
+ * @constructor
+ */
+goog.math.interpolator.Pchip1 = function() {
+  goog.base(this);
+};
+goog.inherits(goog.math.interpolator.Pchip1, goog.math.interpolator.Spline1);
+
+
+/** @override */
+goog.math.interpolator.Pchip1.prototype.computeDerivatives = function(
+    dx, slope) {
+  var len = dx.length;
+  var deriv = new Array(len + 1);
+  for (var i = 1; i < len; ++i) {
+    if (goog.math.sign(slope[i - 1]) * goog.math.sign(slope[i]) <= 0) {
+      deriv[i] = 0;
+    } else {
+      var w1 = 2 * dx[i] + dx[i - 1];
+      var w2 = dx[i] + 2 * dx[i - 1];
+      deriv[i] = (w1 + w2) / (w1 / slope[i - 1] + w2 / slope[i]);
+    }
+  }
+  deriv[0] = this.computeDerivativeAtBoundary_(
+      dx[0], dx[1], slope[0], slope[1]);
+  deriv[len] = this.computeDerivativeAtBoundary_(
+      dx[len - 1], dx[len - 2], slope[len - 1], slope[len - 2]);
+  return deriv;
+};
+
+
+/**
+ * Computes the derivative of a data point at a boundary.
+ * @param {number} dx0 The spacing of the 1st data point.
+ * @param {number} dx1 The spacing of the 2nd data point.
+ * @param {number} slope0 The slope of the 1st data point.
+ * @param {number} slope1 The slope of the 2nd data point.
+ * @return {number} The derivative at the 1st data point.
+ * @private
+ */
+goog.math.interpolator.Pchip1.prototype.computeDerivativeAtBoundary_ = function(
+    dx0, dx1, slope0, slope1) {
+  var deriv = ((2 * dx0 + dx1) * slope0 - dx0 * slope1) / (dx0 + dx1);
+  if (goog.math.sign(deriv) != goog.math.sign(slope0)) {
+    deriv = 0;
+  } else if (goog.math.sign(slope0) != goog.math.sign(slope1) &&
+      Math.abs(deriv) > Math.abs(3 * slope0)) {
+    deriv = 3 * slope0;
+  }
+  return deriv;
+};