/* * Copyright (C) 2015 Jared Boone, ShareBrained Technology, Inc. * * This file is part of PortaPack. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2, or (at your option) * any later version. * * This program 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 General Public License * along with this program; see the file COPYING. If not, write to * the Free Software Foundation, Inc., 51 Franklin Street, * Boston, MA 02110-1301, USA. */ #ifndef __SINE_TABLE_H__ #define __SINE_TABLE_H__ // TODO: Including only for pi. Need separate math.hpp... #include "complex.hpp" #include #include /* import numpy length = 256 w = numpy.arange(length, dtype=numpy.float64) * (2 * numpy.pi / length) v = numpy.sin(w) print(v) */ constexpr uint16_t sine_table_f32_period = 256; // periode is 256 . means sine_table_f32[0]= sine_table_f32[0+256], sine_table_f32[1]=sine_table_f32[1+256] (those two added manualy) // Then table has 257 values , [0,..255] + [256] and [257], those two are used when we interpolate[255] with [255+1], and [256] with [256+1] // [256] index is needed in the function sin_f32() when we are inputing very small radian values , example , sin_f32((-1e-14) in radians) static constexpr std::array sine_table_f32{ 0.00000000e+00, 2.45412285e-02, 4.90676743e-02, 7.35645636e-02, 9.80171403e-02, 1.22410675e-01, 1.46730474e-01, 1.70961889e-01, 1.95090322e-01, 2.19101240e-01, 2.42980180e-01, 2.66712757e-01, 2.90284677e-01, 3.13681740e-01, 3.36889853e-01, 3.59895037e-01, 3.82683432e-01, 4.05241314e-01, 4.27555093e-01, 4.49611330e-01, 4.71396737e-01, 4.92898192e-01, 5.14102744e-01, 5.34997620e-01, 5.55570233e-01, 5.75808191e-01, 5.95699304e-01, 6.15231591e-01, 6.34393284e-01, 6.53172843e-01, 6.71558955e-01, 6.89540545e-01, 7.07106781e-01, 7.24247083e-01, 7.40951125e-01, 7.57208847e-01, 7.73010453e-01, 7.88346428e-01, 8.03207531e-01, 8.17584813e-01, 8.31469612e-01, 8.44853565e-01, 8.57728610e-01, 8.70086991e-01, 8.81921264e-01, 8.93224301e-01, 9.03989293e-01, 9.14209756e-01, 9.23879533e-01, 9.32992799e-01, 9.41544065e-01, 9.49528181e-01, 9.56940336e-01, 9.63776066e-01, 9.70031253e-01, 9.75702130e-01, 9.80785280e-01, 9.85277642e-01, 9.89176510e-01, 9.92479535e-01, 9.95184727e-01, 9.97290457e-01, 9.98795456e-01, 9.99698819e-01, 1.00000000e+00, 9.99698819e-01, 9.98795456e-01, 9.97290457e-01, 9.95184727e-01, 9.92479535e-01, 9.89176510e-01, 9.85277642e-01, 9.80785280e-01, 9.75702130e-01, 9.70031253e-01, 9.63776066e-01, 9.56940336e-01, 9.49528181e-01, 9.41544065e-01, 9.32992799e-01, 9.23879533e-01, 9.14209756e-01, 9.03989293e-01, 8.93224301e-01, 8.81921264e-01, 8.70086991e-01, 8.57728610e-01, 8.44853565e-01, 8.31469612e-01, 8.17584813e-01, 8.03207531e-01, 7.88346428e-01, 7.73010453e-01, 7.57208847e-01, 7.40951125e-01, 7.24247083e-01, 7.07106781e-01, 6.89540545e-01, 6.71558955e-01, 6.53172843e-01, 6.34393284e-01, 6.15231591e-01, 5.95699304e-01, 5.75808191e-01, 5.55570233e-01, 5.34997620e-01, 5.14102744e-01, 4.92898192e-01, 4.71396737e-01, 4.49611330e-01, 4.27555093e-01, 4.05241314e-01, 3.82683432e-01, 3.59895037e-01, 3.36889853e-01, 3.13681740e-01, 2.90284677e-01, 2.66712757e-01, 2.42980180e-01, 2.19101240e-01, 1.95090322e-01, 1.70961889e-01, 1.46730474e-01, 1.22410675e-01, 9.80171403e-02, 7.35645636e-02, 4.90676743e-02, 2.45412285e-02, 1.22464680e-16, -2.45412285e-02, -4.90676743e-02, -7.35645636e-02, -9.80171403e-02, -1.22410675e-01, -1.46730474e-01, -1.70961889e-01, -1.95090322e-01, -2.19101240e-01, -2.42980180e-01, -2.66712757e-01, -2.90284677e-01, -3.13681740e-01, -3.36889853e-01, -3.59895037e-01, -3.82683432e-01, -4.05241314e-01, -4.27555093e-01, -4.49611330e-01, -4.71396737e-01, -4.92898192e-01, -5.14102744e-01, -5.34997620e-01, -5.55570233e-01, -5.75808191e-01, -5.95699304e-01, -6.15231591e-01, -6.34393284e-01, -6.53172843e-01, -6.71558955e-01, -6.89540545e-01, -7.07106781e-01, -7.24247083e-01, -7.40951125e-01, -7.57208847e-01, -7.73010453e-01, -7.88346428e-01, -8.03207531e-01, -8.17584813e-01, -8.31469612e-01, -8.44853565e-01, -8.57728610e-01, -8.70086991e-01, -8.81921264e-01, -8.93224301e-01, -9.03989293e-01, -9.14209756e-01, -9.23879533e-01, -9.32992799e-01, -9.41544065e-01, -9.49528181e-01, -9.56940336e-01, -9.63776066e-01, -9.70031253e-01, -9.75702130e-01, -9.80785280e-01, -9.85277642e-01, -9.89176510e-01, -9.92479535e-01, -9.95184727e-01, -9.97290457e-01, -9.98795456e-01, -9.99698819e-01, -1.00000000e+00, -9.99698819e-01, -9.98795456e-01, -9.97290457e-01, -9.95184727e-01, -9.92479535e-01, -9.89176510e-01, -9.85277642e-01, -9.80785280e-01, -9.75702130e-01, -9.70031253e-01, -9.63776066e-01, -9.56940336e-01, -9.49528181e-01, -9.41544065e-01, -9.32992799e-01, -9.23879533e-01, -9.14209756e-01, -9.03989293e-01, -8.93224301e-01, -8.81921264e-01, -8.70086991e-01, -8.57728610e-01, -8.44853565e-01, -8.31469612e-01, -8.17584813e-01, -8.03207531e-01, -7.88346428e-01, -7.73010453e-01, -7.57208847e-01, -7.40951125e-01, -7.24247083e-01, -7.07106781e-01, -6.89540545e-01, -6.71558955e-01, -6.53172843e-01, -6.34393284e-01, -6.15231591e-01, -5.95699304e-01, -5.75808191e-01, -5.55570233e-01, -5.34997620e-01, -5.14102744e-01, -4.92898192e-01, -4.71396737e-01, -4.49611330e-01, -4.27555093e-01, -4.05241314e-01, -3.82683432e-01, -3.59895037e-01, -3.36889853e-01, -3.13681740e-01, -2.90284677e-01, -2.66712757e-01, -2.42980180e-01, -2.19101240e-01, -1.95090322e-01, -1.70961889e-01, -1.46730474e-01, -1.22410675e-01, -9.80171403e-02, -7.35645636e-02, -4.90676743e-02, -2.45412285e-02, 0.00000000e+00, 2.45412285e-02 }; inline float sin_f32(const float w) { const float x = w / (2 * pi); // normalization const float x_frac = x - std::floor(x); // [0, 1] const float n = x_frac * sine_table_f32_period; const uint16_t n_int = static_cast(n); const float n_frac = n - n_int; const float p0 = sine_table_f32[n_int]; const float p1 = sine_table_f32[n_int + 1]; const float diff = p1 - p0; const float result = p0 + n_frac * diff; // linear interpolation return result; } #endif/*__SINE_TABLE_H__*/