Laxmi Kant Tiwari
CMSIS DSP Lib
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Diff: cmsis_dsp/FastMathFunctions/arm_sin_f32.c
- Revision:
- 1:fdd22bb7aa52
- Child:
- 2:da51fb522205
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/cmsis_dsp/FastMathFunctions/arm_sin_f32.c Wed Nov 28 12:30:09 2012 +0000
@@ -0,0 +1,281 @@
+/* ----------------------------------------------------------------------
+* Copyright (C) 2010 ARM Limited. All rights reserved.
+*
+* $Date: 15. February 2012
+* $Revision: V1.1.0
+*
+* Project: CMSIS DSP Library
+* Title: arm_sin_f32.c
+*
+* Description: Fast sine calculation for floating-point values.
+*
+* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
+*
+* Version 1.1.0 2012/02/15
+* Updated with more optimizations, bug fixes and minor API changes.
+*
+* Version 1.0.10 2011/7/15
+* Big Endian support added and Merged M0 and M3/M4 Source code.
+*
+* Version 1.0.3 2010/11/29
+* Re-organized the CMSIS folders and updated documentation.
+*
+* Version 1.0.2 2010/11/11
+* Documentation updated.
+*
+* Version 1.0.1 2010/10/05
+* Production release and review comments incorporated.
+*
+* Version 1.0.0 2010/09/20
+* Production release and review comments incorporated.
+* -------------------------------------------------------------------- */
+
+#include "arm_math.h"
+
+/**
+ * @ingroup groupFastMath
+ */
+
+/**
+ * @defgroup sin Sine
+ *
+ * Computes the trigonometric sine function using a combination of table lookup
+ * and cubic interpolation. There are separate functions for
+ * Q15, Q31, and floating-point data types.
+ * The input to the floating-point version is in radians while the
+ * fixed-point Q15 and Q31 have a scaled input with the range
+ * [0 +0.9999] mapping to [0 2*pi), Where range excludes 2*pi.
+ *
+ * The implementation is based on table lookup using 256 values together with cubic interpolation.
+ * The steps used are:
+ * -# Calculation of the nearest integer table index
+ * -# Fetch the four table values a, b, c, and d
+ * -# Compute the fractional portion (fract) of the table index.
+ * -# Calculation of wa, wb, wc, wd
+ * -# The final result equals <code>a*wa + b*wb + c*wc + d*wd</code>
+ *
+ * where
+ * <pre>
+ * a=Table[index-1];
+ * b=Table[index+0];
+ * c=Table[index+1];
+ * d=Table[index+2];
+ * </pre>
+ * and
+ * <pre>
+ * wa=-(1/6)*fract.^3 + (1/2)*fract.^2 - (1/3)*fract;
+ * wb=(1/2)*fract.^3 - fract.^2 - (1/2)*fract + 1;
+ * wc=-(1/2)*fract.^3+(1/2)*fract.^2+fract;
+ * wd=(1/6)*fract.^3 - (1/6)*fract;
+ * </pre>
+ */
+
+/**
+ * @addtogroup sin
+ * @{
+ */
+
+
+/**
+ * \par
+ * Example code for Generation of Floating-point Sin Table:
+ * tableSize = 256;
+ * <pre>for(n = -1; n < (tableSize + 1); n++)
+ * {
+ * sinTable[n+1]=sin(2*pi*n/tableSize);
+ * }</pre>
+ * \par
+ * where pi value is 3.14159265358979
+ */
+
+static const float32_t sinTable[259] = {
+ -0.024541229009628296f, 0.000000000000000000f, 0.024541229009628296f,
+ 0.049067676067352295f, 0.073564566671848297f, 0.098017141222953796f,
+ 0.122410677373409270f, 0.146730467677116390f,
+ 0.170961886644363400f, 0.195090323686599730f, 0.219101235270500180f,
+ 0.242980182170867920f, 0.266712754964828490f, 0.290284663438797000f,
+ 0.313681751489639280f, 0.336889863014221190f,
+ 0.359895050525665280f, 0.382683426141738890f, 0.405241310596466060f,
+ 0.427555084228515630f, 0.449611335992813110f, 0.471396744251251220f,
+ 0.492898195981979370f, 0.514102756977081300f,
+ 0.534997642040252690f, 0.555570244789123540f, 0.575808167457580570f,
+ 0.595699310302734380f, 0.615231573581695560f, 0.634393274784088130f,
+ 0.653172850608825680f, 0.671558976173400880f,
+ 0.689540565013885500f, 0.707106769084930420f, 0.724247097969055180f,
+ 0.740951120853424070f, 0.757208824157714840f, 0.773010432720184330f,
+ 0.788346409797668460f, 0.803207516670227050f,
+ 0.817584812641143800f, 0.831469595432281490f, 0.844853579998016360f,
+ 0.857728600502014160f, 0.870086967945098880f, 0.881921291351318360f,
+ 0.893224298954010010f, 0.903989315032958980f,
+ 0.914209783077239990f, 0.923879504203796390f, 0.932992815971374510f,
+ 0.941544055938720700f, 0.949528157711029050f, 0.956940352916717530f,
+ 0.963776051998138430f, 0.970031261444091800f,
+ 0.975702106952667240f, 0.980785250663757320f, 0.985277652740478520f,
+ 0.989176511764526370f, 0.992479562759399410f, 0.995184719562530520f,
+ 0.997290432453155520f, 0.998795449733734130f,
+ 0.999698817729949950f, 1.000000000000000000f, 0.999698817729949950f,
+ 0.998795449733734130f, 0.997290432453155520f, 0.995184719562530520f,
+ 0.992479562759399410f, 0.989176511764526370f,
+ 0.985277652740478520f, 0.980785250663757320f, 0.975702106952667240f,
+ 0.970031261444091800f, 0.963776051998138430f, 0.956940352916717530f,
+ 0.949528157711029050f, 0.941544055938720700f,
+ 0.932992815971374510f, 0.923879504203796390f, 0.914209783077239990f,
+ 0.903989315032958980f, 0.893224298954010010f, 0.881921291351318360f,
+ 0.870086967945098880f, 0.857728600502014160f,
+ 0.844853579998016360f, 0.831469595432281490f, 0.817584812641143800f,
+ 0.803207516670227050f, 0.788346409797668460f, 0.773010432720184330f,
+ 0.757208824157714840f, 0.740951120853424070f,
+ 0.724247097969055180f, 0.707106769084930420f, 0.689540565013885500f,
+ 0.671558976173400880f, 0.653172850608825680f, 0.634393274784088130f,
+ 0.615231573581695560f, 0.595699310302734380f,
+ 0.575808167457580570f, 0.555570244789123540f, 0.534997642040252690f,
+ 0.514102756977081300f, 0.492898195981979370f, 0.471396744251251220f,
+ 0.449611335992813110f, 0.427555084228515630f,
+ 0.405241310596466060f, 0.382683426141738890f, 0.359895050525665280f,
+ 0.336889863014221190f, 0.313681751489639280f, 0.290284663438797000f,
+ 0.266712754964828490f, 0.242980182170867920f,
+ 0.219101235270500180f, 0.195090323686599730f, 0.170961886644363400f,
+ 0.146730467677116390f, 0.122410677373409270f, 0.098017141222953796f,
+ 0.073564566671848297f, 0.049067676067352295f,
+ 0.024541229009628296f, 0.000000000000000122f, -0.024541229009628296f,
+ -0.049067676067352295f, -0.073564566671848297f, -0.098017141222953796f,
+ -0.122410677373409270f, -0.146730467677116390f,
+ -0.170961886644363400f, -0.195090323686599730f, -0.219101235270500180f,
+ -0.242980182170867920f, -0.266712754964828490f, -0.290284663438797000f,
+ -0.313681751489639280f, -0.336889863014221190f,
+ -0.359895050525665280f, -0.382683426141738890f, -0.405241310596466060f,
+ -0.427555084228515630f, -0.449611335992813110f, -0.471396744251251220f,
+ -0.492898195981979370f, -0.514102756977081300f,
+ -0.534997642040252690f, -0.555570244789123540f, -0.575808167457580570f,
+ -0.595699310302734380f, -0.615231573581695560f, -0.634393274784088130f,
+ -0.653172850608825680f, -0.671558976173400880f,
+ -0.689540565013885500f, -0.707106769084930420f, -0.724247097969055180f,
+ -0.740951120853424070f, -0.757208824157714840f, -0.773010432720184330f,
+ -0.788346409797668460f, -0.803207516670227050f,
+ -0.817584812641143800f, -0.831469595432281490f, -0.844853579998016360f,
+ -0.857728600502014160f, -0.870086967945098880f, -0.881921291351318360f,
+ -0.893224298954010010f, -0.903989315032958980f,
+ -0.914209783077239990f, -0.923879504203796390f, -0.932992815971374510f,
+ -0.941544055938720700f, -0.949528157711029050f, -0.956940352916717530f,
+ -0.963776051998138430f, -0.970031261444091800f,
+ -0.975702106952667240f, -0.980785250663757320f, -0.985277652740478520f,
+ -0.989176511764526370f, -0.992479562759399410f, -0.995184719562530520f,
+ -0.997290432453155520f, -0.998795449733734130f,
+ -0.999698817729949950f, -1.000000000000000000f, -0.999698817729949950f,
+ -0.998795449733734130f, -0.997290432453155520f, -0.995184719562530520f,
+ -0.992479562759399410f, -0.989176511764526370f,
+ -0.985277652740478520f, -0.980785250663757320f, -0.975702106952667240f,
+ -0.970031261444091800f, -0.963776051998138430f, -0.956940352916717530f,
+ -0.949528157711029050f, -0.941544055938720700f,
+ -0.932992815971374510f, -0.923879504203796390f, -0.914209783077239990f,
+ -0.903989315032958980f, -0.893224298954010010f, -0.881921291351318360f,
+ -0.870086967945098880f, -0.857728600502014160f,
+ -0.844853579998016360f, -0.831469595432281490f, -0.817584812641143800f,
+ -0.803207516670227050f, -0.788346409797668460f, -0.773010432720184330f,
+ -0.757208824157714840f, -0.740951120853424070f,
+ -0.724247097969055180f, -0.707106769084930420f, -0.689540565013885500f,
+ -0.671558976173400880f, -0.653172850608825680f, -0.634393274784088130f,
+ -0.615231573581695560f, -0.595699310302734380f,
+ -0.575808167457580570f, -0.555570244789123540f, -0.534997642040252690f,
+ -0.514102756977081300f, -0.492898195981979370f, -0.471396744251251220f,
+ -0.449611335992813110f, -0.427555084228515630f,
+ -0.405241310596466060f, -0.382683426141738890f, -0.359895050525665280f,
+ -0.336889863014221190f, -0.313681751489639280f, -0.290284663438797000f,
+ -0.266712754964828490f, -0.242980182170867920f,
+ -0.219101235270500180f, -0.195090323686599730f, -0.170961886644363400f,
+ -0.146730467677116390f, -0.122410677373409270f, -0.098017141222953796f,
+ -0.073564566671848297f, -0.049067676067352295f,
+ -0.024541229009628296f, -0.000000000000000245f, 0.024541229009628296f
+};
+
+
+/**
+ * @brief Fast approximation to the trigonometric sine function for floating-point data.
+ * @param[in] x input value in radians.
+ * @return sin(x).
+ */
+
+float32_t arm_sin_f32(
+ float32_t x)
+{
+ float32_t sinVal, fract, in; /* Temporary variables for input, output */
+ int32_t index; /* Index variable */
+ uint32_t tableSize = (uint32_t) TABLE_SIZE; /* Initialise tablesize */
+ float32_t wa, wb, wc, wd; /* Cubic interpolation coefficients */
+ float32_t a, b, c, d; /* Four nearest output values */
+ float32_t *tablePtr; /* Pointer to table */
+ int32_t n;
+ float32_t fractsq, fractby2, fractby6, fractby3, fractsqby2;
+ float32_t oneminusfractby2;
+ float32_t frby2xfrsq, frby6xfrsq;
+
+ /* input x is in radians */
+ /* Scale the input to [0 1] range from [0 2*PI] , divide input by 2*pi */
+ in = x * 0.159154943092f;
+
+ /* Calculation of floor value of input */
+ n = (int32_t) in;
+
+ /* Make negative values towards -infinity */
+ if(x < 0.0f)
+ {
+ n = n - 1;
+ }
+
+ /* Map input value to [0 1] */
+ in = in - (float32_t) n;
+
+ /* Calculation of index of the table */
+ index = (uint32_t) (tableSize * in);
+
+ /* fractional value calculation */
+ fract = ((float32_t) tableSize * in) - (float32_t) index;
+
+ /* Checking min and max index of table */
+ if(index < 0)
+ {
+ index = 0;
+ }
+ else if(index > 256)
+ {
+ index = 256;
+ }
+
+ /* Initialise table pointer */
+ tablePtr = (float32_t *) & sinTable[index];
+
+ /* Read four nearest values of input value from the sin table */
+ a = tablePtr[0];
+ b = tablePtr[1];
+ c = tablePtr[2];
+ d = tablePtr[3];
+
+ /* Cubic interpolation process */
+ fractsq = fract * fract;
+ fractby2 = fract * 0.5f;
+ fractby6 = fract * 0.166666667f;
+ fractby3 = fract * 0.3333333333333f;
+ fractsqby2 = fractsq * 0.5f;
+ frby2xfrsq = (fractby2) * fractsq;
+ frby6xfrsq = (fractby6) * fractsq;
+ oneminusfractby2 = 1.0f - fractby2;
+ wb = fractsqby2 - fractby3;
+ wc = (fractsqby2 + fract);
+ wa = wb - frby6xfrsq;
+ wb = frby2xfrsq - fractsq;
+ sinVal = wa * a;
+ wc = wc - frby2xfrsq;
+ wd = (frby6xfrsq) - fractby6;
+ wb = wb + oneminusfractby2;
+
+ /* Calculate sin value */
+ sinVal = (sinVal + (b * wb)) + ((c * wc) + (d * wd));
+
+ /* Return the output value */
+ return (sinVal);
+
+}
+
+/**
+ * @} end of sin group
+ */