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Diffstat (limited to 'Drivers/CMSIS/DSP/Source/ControllerFunctions/arm_sin_cos_f32.c')
| -rw-r--r-- | Drivers/CMSIS/DSP/Source/ControllerFunctions/arm_sin_cos_f32.c | 146 |
1 files changed, 146 insertions, 0 deletions
diff --git a/Drivers/CMSIS/DSP/Source/ControllerFunctions/arm_sin_cos_f32.c b/Drivers/CMSIS/DSP/Source/ControllerFunctions/arm_sin_cos_f32.c new file mode 100644 index 0000000..438e4d4 --- /dev/null +++ b/Drivers/CMSIS/DSP/Source/ControllerFunctions/arm_sin_cos_f32.c @@ -0,0 +1,146 @@ +/* ----------------------------------------------------------------------
+ * Project: CMSIS DSP Library
+ * Title: arm_sin_cos_f32.c
+ * Description: Sine and Cosine calculation for floating-point values
+ *
+ * $Date: 18. March 2019
+ * $Revision: V1.6.0
+ *
+ * Target Processor: Cortex-M cores
+ * -------------------------------------------------------------------- */
+/*
+ * Copyright (C) 2010-2019 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 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 result is accurate to 5 digits after the decimal point.
+
+ 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 processed sine output
+ @param[out] pCosVal points to processed cosine output
+ @return none
+ */
+
+void arm_sin_cos_f32(
+ float32_t theta,
+ float32_t * pSinVal,
+ float32_t * pCosVal)
+{
+ float32_t fract, in; /* Temporary input, output variables */
+ uint16_t indexS, indexC; /* Index variable */
+ float32_t f1, f2, d1, d2; /* Two nearest output values */
+ float32_t Dn, Df;
+ float32_t temp, findex;
+
+ /* input x is in degrees */
+ /* Scale input, divide input by 360, for cosine add 0.25 (pi/2) to read sine table */
+ in = theta * 0.00277777777778f;
+
+ if (in < 0.0f)
+ {
+ in = -in;
+ }
+
+ in = in - (int32_t)in;
+
+ /* Calculate the nearest index */
+ findex = (float32_t)FAST_MATH_TABLE_SIZE * in;
+ indexS = ((uint16_t)findex) & 0x1ff;
+ indexC = (indexS + (FAST_MATH_TABLE_SIZE / 4)) & 0x1ff;
+
+ /* Calculation of fractional value */
+ fract = findex - (float32_t) indexS;
+
+ /* Read two nearest values of input value from the cos & sin tables */
+ f1 = sinTable_f32[indexC ];
+ f2 = sinTable_f32[indexC+1];
+ d1 = -sinTable_f32[indexS ];
+ d2 = -sinTable_f32[indexS+1];
+
+ temp = (1.0f - fract) * f1 + fract * f2;
+
+ 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 ];
+ f2 = sinTable_f32[indexS+1];
+ d1 = sinTable_f32[indexC ];
+ d2 = sinTable_f32[indexC+1];
+
+ temp = (1.0f - fract) * f1 + fract * f2;
+
+ 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;
+
+ if (theta < 0.0f)
+ {
+ *pSinVal = -*pSinVal;
+ }
+}
+
+/**
+ @} end of SinCos group
+ */
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