Laxmi Kant Tiwari / mbed-dsp

CMSIS DSP Lib

Fork of mbed-dsp by mbed official

cmsis_dsp/FastMathFunctions/arm_cos_q31.c@4:9cee975aadce, 2014-06-23 (annotated)

Committer:
mbed_official
Date:
Mon Jun 23 09:30:09 2014 +0100
Revision:
4:9cee975aadce
Parent:
3:7a284390b0ce 
Synchronized with git revision 6e7c7bcec41226f536474daae3c13d49e4c0e865



Full URL: https://github.com/mbedmicro/mbed/commit/6e7c7bcec41226f536474daae3c13d49e4c0e865/



Fix signed unsigned compare in dsp library

Who changed what in which revision?

UserRevisionLine numberNew contents of line
emilmont 1:fdd22bb7aa52 1 /* ----------------------------------------------------------------------
mbed_official 3:7a284390b0ce 2 * Copyright (C) 2010-2013 ARM Limited. All rights reserved.
emilmont 1:fdd22bb7aa52 3 *
mbed_official 3:7a284390b0ce 4 * $Date: 17. January 2013
mbed_official 3:7a284390b0ce 5 * $Revision: V1.4.1
emilmont 1:fdd22bb7aa52 6 *
emilmont 2:da51fb522205 7 * Project: CMSIS DSP Library
emilmont 2:da51fb522205 8 * Title: arm_cos_q31.c
emilmont 1:fdd22bb7aa52 9 *
emilmont 2:da51fb522205 10 * Description: Fast cosine calculation for Q31 values.
emilmont 1:fdd22bb7aa52 11 *
emilmont 1:fdd22bb7aa52 12 * Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
emilmont 1:fdd22bb7aa52 13 *
mbed_official 3:7a284390b0ce 14 * Redistribution and use in source and binary forms, with or without
mbed_official 3:7a284390b0ce 15 * modification, are permitted provided that the following conditions
mbed_official 3:7a284390b0ce 16 * are met:
mbed_official 3:7a284390b0ce 17 * - Redistributions of source code must retain the above copyright
mbed_official 3:7a284390b0ce 18 * notice, this list of conditions and the following disclaimer.
mbed_official 3:7a284390b0ce 19 * - Redistributions in binary form must reproduce the above copyright
mbed_official 3:7a284390b0ce 20 * notice, this list of conditions and the following disclaimer in
mbed_official 3:7a284390b0ce 21 * the documentation and/or other materials provided with the
mbed_official 3:7a284390b0ce 22 * distribution.
mbed_official 3:7a284390b0ce 23 * - Neither the name of ARM LIMITED nor the names of its contributors
mbed_official 3:7a284390b0ce 24 * may be used to endorse or promote products derived from this
mbed_official 3:7a284390b0ce 25 * software without specific prior written permission.
mbed_official 3:7a284390b0ce 26 *
mbed_official 3:7a284390b0ce 27 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
mbed_official 3:7a284390b0ce 28 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
mbed_official 3:7a284390b0ce 29 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
mbed_official 3:7a284390b0ce 30 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
mbed_official 3:7a284390b0ce 31 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
mbed_official 3:7a284390b0ce 32 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
mbed_official 3:7a284390b0ce 33 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
mbed_official 3:7a284390b0ce 34 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
mbed_official 3:7a284390b0ce 35 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
mbed_official 3:7a284390b0ce 36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
mbed_official 3:7a284390b0ce 37 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
mbed_official 3:7a284390b0ce 38 * POSSIBILITY OF SUCH DAMAGE.
emilmont 1:fdd22bb7aa52 39 * -------------------------------------------------------------------- */
emilmont 1:fdd22bb7aa52 40
emilmont 1:fdd22bb7aa52 41 #include "arm_math.h"
emilmont 1:fdd22bb7aa52 42
emilmont 1:fdd22bb7aa52 43 /**
emilmont 1:fdd22bb7aa52 44 * @ingroup groupFastMath
emilmont 1:fdd22bb7aa52 45 */
emilmont 1:fdd22bb7aa52 46
emilmont 1:fdd22bb7aa52 47 /**
emilmont 1:fdd22bb7aa52 48 * @addtogroup cos
emilmont 1:fdd22bb7aa52 49 * @{
emilmont 1:fdd22bb7aa52 50 */
emilmont 1:fdd22bb7aa52 51
emilmont 1:fdd22bb7aa52 52 /**
emilmont 1:fdd22bb7aa52 53 * \par
mbed_official 3:7a284390b0ce 54 * Table values are in Q31 (1.31 fixed-point format) and generation is done in
mbed_official 3:7a284390b0ce 55 * three steps. First, generate cos values in floating point:
mbed_official 3:7a284390b0ce 56 * <pre>
emilmont 1:fdd22bb7aa52 57 * tableSize = 256;
mbed_official 3:7a284390b0ce 58 * for(n = -1; n < (tableSize + 1); n++)
emilmont 1:fdd22bb7aa52 59 * {
emilmont 2:da51fb522205 60 * cosTable[n+1]= cos(2*pi*n/tableSize);
emilmont 1:fdd22bb7aa52 61 * } </pre>
emilmont 1:fdd22bb7aa52 62 * where pi value is 3.14159265358979
emilmont 1:fdd22bb7aa52 63 * \par
mbed_official 3:7a284390b0ce 64 * Second, convert floating-point to Q31 (Fixed point):
emilmont 2:da51fb522205 65 * (cosTable[i] * pow(2, 31))
emilmont 1:fdd22bb7aa52 66 * \par
mbed_official 3:7a284390b0ce 67 * Finally, round to the nearest integer value:
emilmont 2:da51fb522205 68 * cosTable[i] += (cosTable[i] > 0 ? 0.5 :-0.5);
emilmont 1:fdd22bb7aa52 69 */
emilmont 1:fdd22bb7aa52 70
emilmont 1:fdd22bb7aa52 71
emilmont 1:fdd22bb7aa52 72 static const q31_t cosTableQ31[259] = {
emilmont 1:fdd22bb7aa52 73 0x7ff62182, 0x7fffffff, 0x7ff62182, 0x7fd8878e, 0x7fa736b4, 0x7f62368f,
emilmont 1:fdd22bb7aa52 74 0x7f0991c4, 0x7e9d55fc,
emilmont 1:fdd22bb7aa52 75 0x7e1d93ea, 0x7d8a5f40, 0x7ce3ceb2, 0x7c29fbee, 0x7b5d039e, 0x7a7d055b,
emilmont 1:fdd22bb7aa52 76 0x798a23b1, 0x78848414,
emilmont 1:fdd22bb7aa52 77 0x776c4edb, 0x7641af3d, 0x7504d345, 0x73b5ebd1, 0x72552c85, 0x70e2cbc6,
emilmont 1:fdd22bb7aa52 78 0x6f5f02b2, 0x6dca0d14,
emilmont 1:fdd22bb7aa52 79 0x6c242960, 0x6a6d98a4, 0x68a69e81, 0x66cf8120, 0x64e88926, 0x62f201ac,
emilmont 1:fdd22bb7aa52 80 0x60ec3830, 0x5ed77c8a,
emilmont 1:fdd22bb7aa52 81 0x5cb420e0, 0x5a82799a, 0x5842dd54, 0x55f5a4d2, 0x539b2af0, 0x5133cc94,
emilmont 1:fdd22bb7aa52 82 0x4ebfe8a5, 0x4c3fdff4,
emilmont 1:fdd22bb7aa52 83 0x49b41533, 0x471cece7, 0x447acd50, 0x41ce1e65, 0x3f1749b8, 0x3c56ba70,
emilmont 1:fdd22bb7aa52 84 0x398cdd32, 0x36ba2014,
emilmont 1:fdd22bb7aa52 85 0x33def287, 0x30fbc54d, 0x2e110a62, 0x2b1f34eb, 0x2826b928, 0x25280c5e,
emilmont 1:fdd22bb7aa52 86 0x2223a4c5, 0x1f19f97b,
emilmont 1:fdd22bb7aa52 87 0x1c0b826a, 0x18f8b83c, 0x15e21445, 0x12c8106f, 0xfab272b, 0xc8bd35e,
emilmont 1:fdd22bb7aa52 88 0x96a9049, 0x647d97c,
emilmont 1:fdd22bb7aa52 89 0x3242abf, 0x0, 0xfcdbd541, 0xf9b82684, 0xf6956fb7, 0xf3742ca2, 0xf054d8d5,
emilmont 1:fdd22bb7aa52 90 0xed37ef91,
emilmont 1:fdd22bb7aa52 91 0xea1debbb, 0xe70747c4, 0xe3f47d96, 0xe0e60685, 0xdddc5b3b, 0xdad7f3a2,
emilmont 1:fdd22bb7aa52 92 0xd7d946d8, 0xd4e0cb15,
emilmont 1:fdd22bb7aa52 93 0xd1eef59e, 0xcf043ab3, 0xcc210d79, 0xc945dfec, 0xc67322ce, 0xc3a94590,
emilmont 1:fdd22bb7aa52 94 0xc0e8b648, 0xbe31e19b,
emilmont 1:fdd22bb7aa52 95 0xbb8532b0, 0xb8e31319, 0xb64beacd, 0xb3c0200c, 0xb140175b, 0xaecc336c,
emilmont 1:fdd22bb7aa52 96 0xac64d510, 0xaa0a5b2e,
emilmont 1:fdd22bb7aa52 97 0xa7bd22ac, 0xa57d8666, 0xa34bdf20, 0xa1288376, 0x9f13c7d0, 0x9d0dfe54,
emilmont 1:fdd22bb7aa52 98 0x9b1776da, 0x99307ee0,
emilmont 1:fdd22bb7aa52 99 0x9759617f, 0x9592675c, 0x93dbd6a0, 0x9235f2ec, 0x90a0fd4e, 0x8f1d343a,
emilmont 1:fdd22bb7aa52 100 0x8daad37b, 0x8c4a142f,
emilmont 1:fdd22bb7aa52 101 0x8afb2cbb, 0x89be50c3, 0x8893b125, 0x877b7bec, 0x8675dc4f, 0x8582faa5,
emilmont 1:fdd22bb7aa52 102 0x84a2fc62, 0x83d60412,
emilmont 1:fdd22bb7aa52 103 0x831c314e, 0x8275a0c0, 0x81e26c16, 0x8162aa04, 0x80f66e3c, 0x809dc971,
emilmont 1:fdd22bb7aa52 104 0x8058c94c, 0x80277872,
emilmont 1:fdd22bb7aa52 105 0x8009de7e, 0x80000000, 0x8009de7e, 0x80277872, 0x8058c94c, 0x809dc971,
emilmont 1:fdd22bb7aa52 106 0x80f66e3c, 0x8162aa04,
emilmont 1:fdd22bb7aa52 107 0x81e26c16, 0x8275a0c0, 0x831c314e, 0x83d60412, 0x84a2fc62, 0x8582faa5,
emilmont 1:fdd22bb7aa52 108 0x8675dc4f, 0x877b7bec,
emilmont 1:fdd22bb7aa52 109 0x8893b125, 0x89be50c3, 0x8afb2cbb, 0x8c4a142f, 0x8daad37b, 0x8f1d343a,
emilmont 1:fdd22bb7aa52 110 0x90a0fd4e, 0x9235f2ec,
emilmont 1:fdd22bb7aa52 111 0x93dbd6a0, 0x9592675c, 0x9759617f, 0x99307ee0, 0x9b1776da, 0x9d0dfe54,
emilmont 1:fdd22bb7aa52 112 0x9f13c7d0, 0xa1288376,
emilmont 1:fdd22bb7aa52 113 0xa34bdf20, 0xa57d8666, 0xa7bd22ac, 0xaa0a5b2e, 0xac64d510, 0xaecc336c,
emilmont 1:fdd22bb7aa52 114 0xb140175b, 0xb3c0200c,
emilmont 1:fdd22bb7aa52 115 0xb64beacd, 0xb8e31319, 0xbb8532b0, 0xbe31e19b, 0xc0e8b648, 0xc3a94590,
emilmont 1:fdd22bb7aa52 116 0xc67322ce, 0xc945dfec,
emilmont 1:fdd22bb7aa52 117 0xcc210d79, 0xcf043ab3, 0xd1eef59e, 0xd4e0cb15, 0xd7d946d8, 0xdad7f3a2,
emilmont 1:fdd22bb7aa52 118 0xdddc5b3b, 0xe0e60685,
emilmont 1:fdd22bb7aa52 119 0xe3f47d96, 0xe70747c4, 0xea1debbb, 0xed37ef91, 0xf054d8d5, 0xf3742ca2,
emilmont 1:fdd22bb7aa52 120 0xf6956fb7, 0xf9b82684,
emilmont 1:fdd22bb7aa52 121 0xfcdbd541, 0x0, 0x3242abf, 0x647d97c, 0x96a9049, 0xc8bd35e, 0xfab272b,
emilmont 1:fdd22bb7aa52 122 0x12c8106f,
emilmont 1:fdd22bb7aa52 123 0x15e21445, 0x18f8b83c, 0x1c0b826a, 0x1f19f97b, 0x2223a4c5, 0x25280c5e,
emilmont 1:fdd22bb7aa52 124 0x2826b928, 0x2b1f34eb,
emilmont 1:fdd22bb7aa52 125 0x2e110a62, 0x30fbc54d, 0x33def287, 0x36ba2014, 0x398cdd32, 0x3c56ba70,
emilmont 1:fdd22bb7aa52 126 0x3f1749b8, 0x41ce1e65,
emilmont 1:fdd22bb7aa52 127 0x447acd50, 0x471cece7, 0x49b41533, 0x4c3fdff4, 0x4ebfe8a5, 0x5133cc94,
emilmont 1:fdd22bb7aa52 128 0x539b2af0, 0x55f5a4d2,
emilmont 1:fdd22bb7aa52 129 0x5842dd54, 0x5a82799a, 0x5cb420e0, 0x5ed77c8a, 0x60ec3830, 0x62f201ac,
emilmont 1:fdd22bb7aa52 130 0x64e88926, 0x66cf8120,
emilmont 1:fdd22bb7aa52 131 0x68a69e81, 0x6a6d98a4, 0x6c242960, 0x6dca0d14, 0x6f5f02b2, 0x70e2cbc6,
emilmont 1:fdd22bb7aa52 132 0x72552c85, 0x73b5ebd1,
emilmont 1:fdd22bb7aa52 133 0x7504d345, 0x7641af3d, 0x776c4edb, 0x78848414, 0x798a23b1, 0x7a7d055b,
emilmont 1:fdd22bb7aa52 134 0x7b5d039e, 0x7c29fbee,
emilmont 1:fdd22bb7aa52 135 0x7ce3ceb2, 0x7d8a5f40, 0x7e1d93ea, 0x7e9d55fc, 0x7f0991c4, 0x7f62368f,
emilmont 1:fdd22bb7aa52 136 0x7fa736b4, 0x7fd8878e,
emilmont 1:fdd22bb7aa52 137 0x7ff62182, 0x7fffffff, 0x7ff62182
emilmont 1:fdd22bb7aa52 138 };
emilmont 1:fdd22bb7aa52 139
emilmont 1:fdd22bb7aa52 140 /**
emilmont 1:fdd22bb7aa52 141 * @brief Fast approximation to the trigonometric cosine function for Q31 data.
emilmont 1:fdd22bb7aa52 142 * @param[in] x Scaled input value in radians.
emilmont 1:fdd22bb7aa52 143 * @return cos(x).
emilmont 1:fdd22bb7aa52 144 *
mbed_official 3:7a284390b0ce 145 * The Q31 input value is in the range [0 +0.9999] and is mapped to a radian
mbed_official 3:7a284390b0ce 146 * value in the range [0 2*pi).
emilmont 1:fdd22bb7aa52 147 */
emilmont 1:fdd22bb7aa52 148
emilmont 1:fdd22bb7aa52 149 q31_t arm_cos_q31(
emilmont 1:fdd22bb7aa52 150 q31_t x)
emilmont 1:fdd22bb7aa52 151 {
emilmont 1:fdd22bb7aa52 152 q31_t cosVal, in, in2; /* Temporary variables for input, output */
emilmont 1:fdd22bb7aa52 153 q31_t wa, wb, wc, wd; /* Cubic interpolation coefficients */
emilmont 1:fdd22bb7aa52 154 q31_t a, b, c, d; /* Four nearest output values */
emilmont 1:fdd22bb7aa52 155 q31_t *tablePtr; /* Pointer to table */
emilmont 1:fdd22bb7aa52 156 q31_t fract, fractCube, fractSquare; /* Temporary values for fractional values */
emilmont 1:fdd22bb7aa52 157 q31_t oneBy6 = 0x15555555; /* Fixed point value of 1/6 */
emilmont 1:fdd22bb7aa52 158 q31_t tableSpacing = TABLE_SPACING_Q31; /* Table spacing */
emilmont 1:fdd22bb7aa52 159 q31_t temp; /* Temporary variable for intermediate process */
emilmont 1:fdd22bb7aa52 160 int32_t index; /* Index variable */
emilmont 1:fdd22bb7aa52 161
emilmont 1:fdd22bb7aa52 162 in = x;
emilmont 1:fdd22bb7aa52 163
emilmont 1:fdd22bb7aa52 164 /* Calculate the nearest index */
emilmont 1:fdd22bb7aa52 165 index = in / tableSpacing;
emilmont 1:fdd22bb7aa52 166
emilmont 1:fdd22bb7aa52 167 /* Calculate the nearest value of input */
emilmont 1:fdd22bb7aa52 168 in2 = ((q31_t) index) * tableSpacing;
emilmont 1:fdd22bb7aa52 169
emilmont 1:fdd22bb7aa52 170 /* Calculation of fractional value */
emilmont 1:fdd22bb7aa52 171 fract = (in - in2) << 8;
emilmont 1:fdd22bb7aa52 172
emilmont 1:fdd22bb7aa52 173 /* fractSquare = fract * fract */
emilmont 1:fdd22bb7aa52 174 fractSquare = ((q31_t) (((q63_t) fract * fract) >> 32));
emilmont 1:fdd22bb7aa52 175 fractSquare = fractSquare << 1;
emilmont 1:fdd22bb7aa52 176
emilmont 1:fdd22bb7aa52 177 /* fractCube = fract * fract * fract */
emilmont 1:fdd22bb7aa52 178 fractCube = ((q31_t) (((q63_t) fractSquare * fract) >> 32));
emilmont 1:fdd22bb7aa52 179 fractCube = fractCube << 1;
emilmont 1:fdd22bb7aa52 180
emilmont 1:fdd22bb7aa52 181 /* Checking min and max index of table */
emilmont 1:fdd22bb7aa52 182 if(index < 0)
emilmont 1:fdd22bb7aa52 183 {
emilmont 1:fdd22bb7aa52 184 index = 0;
emilmont 1:fdd22bb7aa52 185 }
emilmont 1:fdd22bb7aa52 186 else if(index > 256)
emilmont 1:fdd22bb7aa52 187 {
emilmont 1:fdd22bb7aa52 188 index = 256;
emilmont 1:fdd22bb7aa52 189 }
emilmont 1:fdd22bb7aa52 190
emilmont 1:fdd22bb7aa52 191 /* Initialise table pointer */
emilmont 1:fdd22bb7aa52 192 tablePtr = (q31_t *) & cosTableQ31[index];
emilmont 1:fdd22bb7aa52 193
emilmont 1:fdd22bb7aa52 194 /* Cubic interpolation process */
emilmont 1:fdd22bb7aa52 195 /* Calculation of wa */
emilmont 1:fdd22bb7aa52 196 /* wa = -(oneBy6)*fractCube + (fractSquare >> 1u) - (0x2AAAAAAA)*fract; */
emilmont 1:fdd22bb7aa52 197 wa = ((q31_t) (((q63_t) oneBy6 * fractCube) >> 32));
emilmont 1:fdd22bb7aa52 198 temp = 0x2AAAAAAA;
emilmont 1:fdd22bb7aa52 199 wa = (q31_t) ((((q63_t) wa << 32) + ((q63_t) temp * fract)) >> 32);
emilmont 1:fdd22bb7aa52 200 wa = -(wa << 1u);
emilmont 1:fdd22bb7aa52 201 wa += (fractSquare >> 1u);
emilmont 1:fdd22bb7aa52 202
emilmont 1:fdd22bb7aa52 203 /* Read first nearest value of output from the cos table */
emilmont 1:fdd22bb7aa52 204 a = *tablePtr++;
emilmont 1:fdd22bb7aa52 205
emilmont 1:fdd22bb7aa52 206 /* cosVal = a*wa */
emilmont 1:fdd22bb7aa52 207 cosVal = ((q31_t) (((q63_t) a * wa) >> 32));
emilmont 1:fdd22bb7aa52 208
emilmont 1:fdd22bb7aa52 209 /* q31(1.31) Fixed point value of 1 */
emilmont 1:fdd22bb7aa52 210 temp = 0x7FFFFFFF;
emilmont 1:fdd22bb7aa52 211
emilmont 1:fdd22bb7aa52 212 /* Calculation of wb */
emilmont 1:fdd22bb7aa52 213 wb = ((fractCube >> 1u) - (fractSquare + (fract >> 1u))) + temp;
emilmont 1:fdd22bb7aa52 214 /* Read second nearest value of output from the cos table */
emilmont 1:fdd22bb7aa52 215 b = *tablePtr++;
emilmont 1:fdd22bb7aa52 216
emilmont 1:fdd22bb7aa52 217 /* cosVal += b*wb */
emilmont 1:fdd22bb7aa52 218 cosVal = (q31_t) ((((q63_t) cosVal << 32) + ((q63_t) b * (wb))) >> 32);
emilmont 1:fdd22bb7aa52 219
emilmont 1:fdd22bb7aa52 220 /* Calculation of wc */
emilmont 1:fdd22bb7aa52 221 wc = -fractCube + fractSquare;
emilmont 1:fdd22bb7aa52 222 wc = (wc >> 1u) + fract;
emilmont 1:fdd22bb7aa52 223 /* Read third nearest values of output value from the cos table */
emilmont 1:fdd22bb7aa52 224 c = *tablePtr++;
emilmont 1:fdd22bb7aa52 225
emilmont 1:fdd22bb7aa52 226 /* cosVal += c*wc */
emilmont 1:fdd22bb7aa52 227 cosVal = (q31_t) ((((q63_t) cosVal << 32) + ((q63_t) c * (wc))) >> 32);
emilmont 1:fdd22bb7aa52 228
emilmont 1:fdd22bb7aa52 229 /* Calculation of wd */
emilmont 1:fdd22bb7aa52 230 /* wd = (oneBy6)*fractCube - (oneBy6)*fract; */
emilmont 1:fdd22bb7aa52 231 fractCube = fractCube - fract;
emilmont 1:fdd22bb7aa52 232 wd = ((q31_t) (((q63_t) oneBy6 * fractCube) >> 32));
emilmont 1:fdd22bb7aa52 233 wd = (wd << 1u);
emilmont 1:fdd22bb7aa52 234
emilmont 1:fdd22bb7aa52 235 /* Read fourth nearest value of output from the cos table */
emilmont 1:fdd22bb7aa52 236 d = *tablePtr++;
emilmont 1:fdd22bb7aa52 237
emilmont 1:fdd22bb7aa52 238 /* cosVal += d*wd; */
emilmont 1:fdd22bb7aa52 239 cosVal = (q31_t) ((((q63_t) cosVal << 32) + ((q63_t) d * (wd))) >> 32);
emilmont 1:fdd22bb7aa52 240
emilmont 1:fdd22bb7aa52 241
emilmont 1:fdd22bb7aa52 242 /* convert cosVal in 2.30 format to 1.31 format */
emilmont 1:fdd22bb7aa52 243 return (__QADD(cosVal, cosVal));
emilmont 1:fdd22bb7aa52 244
emilmont 1:fdd22bb7aa52 245 }
emilmont 1:fdd22bb7aa52 246
emilmont 1:fdd22bb7aa52 247 /**
emilmont 1:fdd22bb7aa52 248 * @} end of cos group
emilmont 1:fdd22bb7aa52 249 */