diff options
Diffstat (limited to 'platform/CMSIS/DSP_Lib/Source/ControllerFunctions/arm_sin_cos_f32.c')
| -rw-r--r-- | platform/CMSIS/DSP_Lib/Source/ControllerFunctions/arm_sin_cos_f32.c | 149 |
1 files changed, 149 insertions, 0 deletions
diff --git a/platform/CMSIS/DSP_Lib/Source/ControllerFunctions/arm_sin_cos_f32.c b/platform/CMSIS/DSP_Lib/Source/ControllerFunctions/arm_sin_cos_f32.c new file mode 100644 index 0000000..0ce0886 --- /dev/null +++ b/platform/CMSIS/DSP_Lib/Source/ControllerFunctions/arm_sin_cos_f32.c @@ -0,0 +1,149 @@ +/* ---------------------------------------------------------------------- +* Copyright (C) 2010-2014 ARM Limited. All rights reserved. +* +* $Date: 12. March 2014 +* $Revision: V1.4.4 +* +* Project: CMSIS DSP Library +* Title: arm_sin_cos_f32.c +* +* Description: Sine and Cosine calculation for floating-point values. +* +* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0 +* +* Redistribution and use in source and binary forms, with or without +* modification, are permitted provided that the following conditions +* are met: +* - Redistributions of source code must retain the above copyright +* notice, this list of conditions and the following disclaimer. +* - Redistributions in binary form must reproduce the above copyright +* notice, this list of conditions and the following disclaimer in +* the documentation and/or other materials provided with the +* distribution. +* - Neither the name of ARM LIMITED nor the names of its contributors +* may be used to endorse or promote products derived from this +* software without specific prior written permission. +* +* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS +* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE +* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, +* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, +* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; +* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER +* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN +* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE +* POSSIBILITY OF SUCH DAMAGE. +* -------------------------------------------------------------------- */ + +#include "arm_math.h" +#include "arm_common_tables.h" + +/** + * @ingroup groupController + */ + +/** + * @defgroup SinCos Sine Cosine + * + * Computes the trigonometric sine and cosine values using a combination of table lookup + * and linear interpolation. + * There are separate functions for Q31 and floating-point data types. + * The input to the floating-point version is in degrees while the + * fixed-point Q31 have a scaled input with the range + * [-1 0.9999] mapping to [-180 +180] degrees. + * + * The floating point function also allows values that are out of the usual range. When this happens, the function will + * take extra time to adjust the input value to the range of [-180 180]. + * + * The implementation is based on table lookup using 360 values together with linear interpolation. + * The steps used are: + * -# Calculation of the nearest integer table index. + * -# Compute the fractional portion (fract) of the input. + * -# Fetch the value corresponding to \c index from sine table to \c y0 and also value from \c index+1 to \c y1. + * -# Sine value is computed as <code> *psinVal = y0 + (fract * (y1 - y0))</code>. + * -# Fetch the value corresponding to \c index from cosine table to \c y0 and also value from \c index+1 to \c y1. + * -# Cosine value is computed as <code> *pcosVal = y0 + (fract * (y1 - y0))</code>. + */ + + /** + * @addtogroup SinCos + * @{ + */ + +/** + * @brief Floating-point sin_cos function. + * @param[in] theta input value in degrees + * @param[out] *pSinVal points to the processed sine output. + * @param[out] *pCosVal points to the processed cos output. + * @return none. + */ + +void arm_sin_cos_f32( + float32_t theta, + float32_t * pSinVal, + float32_t * pCosVal) +{ + float32_t fract, in; /* Temporary variables for input, output */ + uint16_t indexS, indexC; /* Index variable */ + float32_t f1, f2, d1, d2; /* Two nearest output values */ + int32_t n; + float32_t findex, Dn, Df, temp; + + /* input x is in degrees */ + /* Scale the input, divide input by 360, for cosine add 0.25 (pi/2) to read sine table */ + in = theta * 0.00277777777778f; + + /* Calculation of floor value of input */ + n = (int32_t) in; + + /* Make negative values towards -infinity */ + if(in < 0.0f) + { + n--; + } + /* Map input value to [0 1] */ + in = in - (float32_t) n; + + /* Calculation of index of the table */ + findex = (float32_t) FAST_MATH_TABLE_SIZE * in; + indexS = ((uint16_t)findex) & 0x1ff; + indexC = (indexS + (FAST_MATH_TABLE_SIZE / 4)) & 0x1ff; + + /* fractional value calculation */ + fract = findex - (float32_t) indexS; + + /* Read two nearest values of input value from the cos & sin tables */ + f1 = sinTable_f32[indexC+0]; + f2 = sinTable_f32[indexC+1]; + d1 = -sinTable_f32[indexS+0]; + d2 = -sinTable_f32[indexS+1]; + + Dn = 0.0122718463030f; // delta between the two points (fixed), in this case 2*pi/FAST_MATH_TABLE_SIZE + Df = f2 - f1; // delta between the values of the functions + temp = Dn*(d1 + d2) - 2*Df; + temp = fract*temp + (3*Df - (d2 + 2*d1)*Dn); + temp = fract*temp + d1*Dn; + + /* Calculation of cosine value */ + *pCosVal = fract*temp + f1; + + /* Read two nearest values of input value from the cos & sin tables */ + f1 = sinTable_f32[indexS+0]; + f2 = sinTable_f32[indexS+1]; + d1 = sinTable_f32[indexC+0]; + d2 = sinTable_f32[indexC+1]; + + Df = f2 - f1; // delta between the values of the functions + temp = Dn*(d1 + d2) - 2*Df; + temp = fract*temp + (3*Df - (d2 + 2*d1)*Dn); + temp = fract*temp + d1*Dn; + + /* Calculation of sine value */ + *pSinVal = fract*temp + f1; +} +/** + * @} end of SinCos group + */ |