/* * Copyright (c) 2015-2019 Sergey Bakhurin * Digital Signal Processing Library [http://dsplib.org] * * This file is part of libdspl-2.0. * * is free software: you can redistribute it and/or modify * it under the terms of the GNU Lesser General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * DSPL is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU Lesser General Public License * along with Foobar. If not, see . */ #include #include #include #include "dspl.h" #ifdef DOXYGEN_ENGLISH #endif #ifdef DOXYGEN_RUSSIAN #endif int DSPL_API low2bp(double* b, double* a, int ord, double w0, double wpl, double wph, double* beta, double* alpha) { double num[3] = {0.0, 0.0, 1.0}; double den[3] = {0.0, 0.0, 0.0}; if(!b || !a || !beta || !alpha) return ERROR_PTR; if(ord < 1) return ERROR_FILTER_ORD; if(w0 <= 0.0 || wpl <= 0.0 || wph <= 0.0 || wph <= wpl) return ERROR_FILTER_FT; num[0] = (wph * wpl) / (w0 * w0); den[1] = (wph - wpl) / w0; return ratcompos(b, a, ord, num, den, 2, beta, alpha); }