/*******************************************************************************
* Copyright (c) 2010 Haifeng Li
*
* 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.
*******************************************************************************/
package smile.wavelet;
/**
* Symlet wavelets. The symlets have compact support and were constructed to
* be as nearly symmetric (least asymmetric) as possible.
*
* @author Haifeng Li
*/
public class SymletWavelet extends Wavelet {
/**
* S8 coefficients
*/
private static final double[] c8 = {
-0.0757657147893407, -0.0296355276459541, 0.4976186676324578,
0.8037387518052163, 0.2978577956055422, -0.0992195435769354,
-0.0126039672622612, 0.0322231006040713
};
/**
* S10 coefficients
*/
private static final double[] c10 = {
0.0195388827353869, -0.0211018340249298, -0.1753280899081075,
0.0166021057644243, 0.6339789634569490, 0.7234076904038076,
0.1993975339769955, -0.0391342493025834, 0.0295194909260734,
0.0273330683451645
};
/**
* S12 coefficients
*/
private static final double[] c12 = {
0.0154041093273377, 0.0034907120843304, -0.1179901111484105,
-0.0483117425859981, 0.4910559419276396, 0.7876411410287941,
0.3379294217282401, -0.0726375227866000, -0.0210602925126954,
0.0447249017707482, 0.0017677118643983, -0.0078007083247650
};
/**
* S14 coefficients
*/
private static final double[] c14 = {
0.0102681767084968, 0.0040102448717033, -0.1078082377036168,
-0.1400472404427030, 0.2886296317509833, 0.7677643170045710,
0.5361019170907720, 0.0174412550871099, -0.0495528349370410,
0.0678926935015971, 0.0305155131659062, -0.0126363034031526,
-0.0010473848889657, 0.0026818145681164
};
/**
* S16 coefficients
*/
private static final double[] c16 = {
-0.0033824159513594, -0.0005421323316355, 0.0316950878103452,
0.0076074873252848, -0.1432942383510542, -0.0612733590679088,
0.4813596512592012, 0.7771857516997478, 0.3644418948359564,
-0.0519458381078751, -0.0272190299168137, 0.0491371796734768,
0.0038087520140601, -0.0149522583367926, -0.0003029205145516,
0.0018899503329007
};
/**
* S18 coefficients
*/
private static final double[] c18 = {
0.0010694900326538, -0.0004731544985879, -0.0102640640276849,
0.0088592674935117, 0.0620777893027638, -0.0182337707798257,
-0.1915508312964873, 0.0352724880359345, 0.6173384491413523,
0.7178970827642257, 0.2387609146074182, -0.0545689584305765,
0.0005834627463312, 0.0302248788579895, -0.0115282102079848,
-0.0132719677815332, 0.0006197808890549, 0.0014009155255716
};
/**
* S20 coefficients
*/
private static final double[] c20 = {
0.0007701598091030, 0.0000956326707837, -0.0086412992759401,
-0.0014653825833465, 0.0459272392237649, 0.0116098939129724,
-0.1594942788575307, -0.0708805358108615, 0.4716906668426588,
0.7695100370143388, 0.3838267612253823, -0.0355367403054689,
-0.0319900568281631, 0.0499949720791560, 0.0057649120455518,
-0.0203549398039460, -0.0008043589345370, 0.0045931735836703,
0.0000570360843390, -0.0004593294205481
};
/**
* Constructor. Create a Symmlet wavelet with n coefficients.
* n = 8, 10, 12, 14, 16, 18, or 20 are supported.
*/
public SymletWavelet(int n) {
super(n == 8 ? c8 :
n == 10 ? c10 :
n == 12 ? c12 :
n == 14 ? c14 :
n == 16 ? c16 :
n == 18 ? c18 :
n == 20 ? c20 : null
);
if ( n < 8 || n > 20 || n % 2 != 0) {
throw new IllegalArgumentException(String.format("n = %d not yet implemented.", n));
}
}
}