| 1 | // Internal dependencies
|
| 2 | import LinAlg from '../math/linalg';
|
| 3 | import Kernel from './base';
|
| 4 |
|
| 5 | class GaussianKernel extends Kernel {
|
| 6 | /**
|
| 7 | * Constructor
|
| 8 | *
|
| 9 | * @param float sigmaSquared Optional. Normalization parameter for exponential
|
| 10 | */
|
| 11 | constructor(sigmaSquared = 1) {
|
| 12 | super();
|
| 13 |
|
| 14 | this.sigmaSquared = sigmaSquared;
|
| 15 | }
|
| 16 |
|
| 17 | /**
|
| 18 | * @see jsmlt.Kernel.Kernel::apply()
|
| 19 | */
|
| 20 | apply(x, y) {
|
| 21 | // Gaussian
|
| 22 | const diff = LinAlg.sum(x, LinAlg.scale(y, -1));
|
| 23 | return Math.exp(-LinAlg.dot(diff, diff) / (2 * this.sigmaSquared));
|
| 24 | }
|
| 25 | }
|
| 26 |
|
| 27 | export default GaussianKernel;
|