| // Copyright 2011 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. |
| |
| goog.provide('goog.math.interpolator.Pchip1Test'); |
| goog.setTestOnly('goog.math.interpolator.Pchip1Test'); |
| |
| goog.require('goog.math.interpolator.Pchip1'); |
| goog.require('goog.testing.jsunit'); |
| |
| function testSpline() { |
| var x = [0, 1, 3, 6, 7]; |
| var y = [0, 0, 0, 0, 0]; |
| |
| for (var i = 0; i < x.length; ++i) { |
| y[i] = Math.sin(x[i]); |
| } |
| var interp = new goog.math.interpolator.Pchip1(); |
| interp.setData(x, y); |
| |
| var xi = [0, 0.5, 1, 2, 3, 4, 5, 6, 7]; |
| var expected = [0, 0.5756, 0.8415, 0.5428, 0.1411, -0.0595, -0.2162, |
| -0.2794, 0.657]; |
| var result = [0, 0, 0, 0, 0, 0, 0, 0, 0]; |
| for (var i = 0; i < xi.length; ++i) { |
| result[i] = interp.interpolate(xi[i]); |
| } |
| assertElementsRoughlyEqual(expected, result, 1e-4); |
| } |
| |
| |
| function testOutOfBounds() { |
| var x = [0, 1, 2, 4]; |
| var y = [2, 5, 4, 2]; |
| var interp = new goog.math.interpolator.Pchip1(); |
| interp.setData(x, y); |
| assertRoughlyEquals(-3, interp.interpolate(-1), 1e-4); |
| assertRoughlyEquals(1, interp.interpolate(5), 1e-4); |
| } |
| |
| |
| function testInverse() { |
| var x = [0, 1, 3, 6, 7]; |
| var y = [0, 2, 7, 8, 10]; |
| |
| var interp = new goog.math.interpolator.Pchip1(); |
| interp.setData(x, y); |
| var invInterp = interp.getInverse(); |
| |
| var xi = [0, 0.5, 1, 2, 3, 4, 5, 6, 7]; |
| var yi = [0, 0.9548, 2, 4.8938, 7, 7.3906, 7.5902, 8, 10]; |
| var expectedX = [0, 0.888, 1, 0.2852, 3, 4.1206, 4.7379, 6, 7]; |
| var resultX = [0, 0, 0, 0, 0, 0, 0, 0, 0]; |
| var resultY = [0, 0, 0, 0, 0, 0, 0, 0, 0]; |
| for (var i = 0; i < xi.length; ++i) { |
| resultY[i] = interp.interpolate(xi[i]); |
| resultX[i] = invInterp.interpolate(yi[i]); |
| } |
| assertElementsRoughlyEqual(expectedX, resultX, 1e-4); |
| assertElementsRoughlyEqual(yi, resultY, 1e-4); |
| } |