Aded CMSIS5 DSP and NN folder. Needs some work
Diff: DSP/source/FastMathFunctions/arm_sin_q31.c
- Revision:
- 0:eedb7d567a5d
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/DSP/source/FastMathFunctions/arm_sin_q31.c Thu Apr 12 01:31:58 2018 +0000 @@ -0,0 +1,76 @@ +/* ---------------------------------------------------------------------- + * Project: CMSIS DSP Library + * Title: arm_sin_q31.c + * Description: Fast sine calculation for Q31 values + * + * $Date: 27. January 2017 + * $Revision: V.1.5.1 + * + * Target Processor: Cortex-M cores + * -------------------------------------------------------------------- */ +/* + * Copyright (C) 2010-2017 ARM Limited or its affiliates. All rights reserved. + * + * SPDX-License-Identifier: Apache-2.0 + * + * 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 + * + * 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. + */ + +#include "arm_math.h" +#include "arm_common_tables.h" + +/** + * @ingroup groupFastMath + */ + + /** + * @addtogroup sin + * @{ + */ + +/** + * @brief Fast approximation to the trigonometric sine function for Q31 data. + * @param[in] x Scaled input value in radians. + * @return sin(x). + * + * The Q31 input value is in the range [0 +0.9999] and is mapped to a radian value in the range [0 2*pi). */ + +q31_t arm_sin_q31( + q31_t x) +{ + q31_t sinVal; /* Temporary variables for input, output */ + int32_t index; /* Index variables */ + q31_t a, b; /* Four nearest output values */ + q31_t fract; /* Temporary values for fractional values */ + + /* Calculate the nearest index */ + index = (uint32_t)x >> FAST_MATH_Q31_SHIFT; + + /* Calculation of fractional value */ + fract = (x - (index << FAST_MATH_Q31_SHIFT)) << 9; + + /* Read two nearest values of input value from the sin table */ + a = sinTable_q31[index]; + b = sinTable_q31[index+1]; + + /* Linear interpolation process */ + sinVal = (q63_t)(0x80000000-fract)*a >> 32; + sinVal = (q31_t)((((q63_t)sinVal << 32) + ((q63_t)fract*b)) >> 32); + + return sinVal << 1; +} + +/** + * @} end of sin group + */ +