tpt_sqrt_q15.c File Reference

#include "tpt_math.h"

Include dependency graph for tpt_sqrt_q15.c:

Macros
#define	SQRT_Q15_TBL2_NUM   128
#define	SQRT_Q15_TBL2_LOG   7
#define	F2Q(f)   ((int)((f) * 0x8000))
	Q15 square root function. More...

Functions
static int32_t	tpt_log2_16b (uint16_t v)
static uint32_t	tpt_ghb_16b (q15_t data)
tpt_status	tpt_sqrt_q15 (q15_t *aOut, q15_t aIn)
	Q15 square root function. More...

Variables
static q15_t	sqrt_q15_tbl1 [16]
	Lookuptable for sqrt(2 ^ N) int i; sqrt_q15_tbl1[0] = 0; for (i = 0; i < 15; i++) { sqrt_q15_tbl1[i + 1]= (int)(sqrt(pow(2.0, i))///sqrt(32768.0)); }. More...
static q15_t	sqrt_q15_tbl2 [128]
	Lookuptable for sqrt(1 <= B < 2) for (i = 0; i < SQRT_Q15_TBL2_NUM; i++) { fin = sqrt(1.0 + i / SQRT_Q15_TBL2_FLOAT_NUM); sqrt_q15_tbl2[i] = fin * 0x4000; }. More...
static q15_t	sqrt_q15_tbl3 [128]
	Lookuptable for sqrt(1 <= B < 2) sqrt_q15_tbl3[0] = 0; for (i = 0; i < 127; i++) { sqrt_q15_tbl3[i + 1] = (int)(sqrt((float)i + 1) More...

Macro Definition Documentation

SQRT_Q15_TBL2_LOG

#define SQRT_Q15_TBL2_LOG   7

SQRT_Q15_TBL2_NUM

#define SQRT_Q15_TBL2_NUM   128

Function Documentation

tpt_ghb_16b()

static uint32_t tpt_ghb_16b ( q15_t  data )

inlinestatic

tpt_log2_16b()

static int32_t tpt_log2_16b ( uint16_t  v )

inlinestatic

Variable Documentation

sqrt_q15_tbl1

q15_t sqrt_q15_tbl1[16]

static

Initial value:

= {
    0x0000, 0x00B5, 0x0100, 0x016A, 0x0200, 0x02D4, 0x0400, 0x05A8,
    0x0800, 0x0B50, 0x1000, 0x16A0, 0x2000, 0x2D41, 0x4000, 0x5A82,
}

Lookuptable for sqrt(2 ^ N) int i; sqrt_q15_tbl1[0] = 0; for (i = 0; i < 15; i++) { sqrt_q15_tbl1[i + 1]= (int)(sqrt(pow(2.0, i))///sqrt(32768.0)); }.

sqrt_q15_tbl2

q15_t sqrt_q15_tbl2[128]

static

Initial value:

= {
    0x4000, 0x403F, 0x407F, 0x40BE, 0x40FE, 0x413C, 0x417B, 0x41BA, 0x41F8,
    0x4236, 0x4273, 0x42B1, 0x42EE, 0x432B, 0x4368, 0x43A5, 0x43E1, 0x441E,
    0x445A, 0x4495, 0x44D1, 0x450C, 0x4548, 0x4583, 0x45BE, 0x45F8, 0x4633,
    0x466D, 0x46A7, 0x46E1, 0x471B, 0x4754, 0x478D, 0x47C7, 0x4800, 0x4838,
    0x4871, 0x48A9, 0x48E2, 0x491A, 0x4952, 0x498A, 0x49C1, 0x49F9, 0x4A30,
    0x4A67, 0x4A9E, 0x4AD5, 0x4B0B, 0x4B42, 0x4B78, 0x4BAE, 0x4BE5, 0x4C1A,
    0x4C50, 0x4C86, 0x4CBB, 0x4CF1, 0x4D26, 0x4D5B, 0x4D90, 0x4DC4, 0x4DF9,
    0x4E2D, 0x4E62, 0x4E96, 0x4ECA, 0x4EFE, 0x4F32, 0x4F65, 0x4F99, 0x4FCC,
    0x5000, 0x5033, 0x5066, 0x5099, 0x50CB, 0x50FE, 0x5130, 0x5163, 0x5195,
    0x51C7, 0x51F9, 0x522B, 0x525D, 0x528F, 0x52C0, 0x52F2, 0x5323, 0x5354,
    0x5385, 0x53B6, 0x53E7, 0x5418, 0x5449, 0x5479, 0x54A9, 0x54DA, 0x550A,
    0x553A, 0x556A, 0x559A, 0x55CA, 0x55FA, 0x5629, 0x5659, 0x5688, 0x56B7,
    0x56E6, 0x5716, 0x5745, 0x5773, 0x57A2, 0x57D1, 0x5800, 0x582E, 0x585C,
    0x588B, 0x58B9, 0x58E7, 0x5915, 0x5943, 0x5971, 0x599F, 0x59CC, 0x59FA,
    0x5A27, 0x5A55,
}

Lookuptable for sqrt(1 <= B < 2) for (i = 0; i < SQRT_Q15_TBL2_NUM; i++) { fin = sqrt(1.0 + i / SQRT_Q15_TBL2_FLOAT_NUM); sqrt_q15_tbl2[i] = fin * 0x4000; }.

sqrt_q15_tbl3

q15_t sqrt_q15_tbl3[128]

static

Initial value:

= {
    0x0000, 0x0005, 0x0007, 0x0009, 0x000b, 0x000c, 0x000d, 0x000e, 0x000f,
    0x0010, 0x0011, 0x0012, 0x0013, 0x0014, 0x0015, 0x0015, 0x0016, 0x0017,
    0x0017, 0x0018, 0x0019, 0x0019, 0x001a, 0x001b, 0x001b, 0x001c, 0x001c,
    0x001d, 0x001d, 0x001e, 0x001e, 0x001f, 0x001f, 0x0020, 0x0020, 0x0021,
    0x0021, 0x0022, 0x0022, 0x0023, 0x0023, 0x0024, 0x0024, 0x0025, 0x0025,
    0x0025, 0x0026, 0x0026, 0x0027, 0x0027, 0x0027, 0x0028, 0x0028, 0x0029,
    0x0029, 0x0029, 0x002a, 0x002a, 0x002b, 0x002b, 0x002b, 0x002c, 0x002c,
    0x002c, 0x002d, 0x002d, 0x002d, 0x002e, 0x002e, 0x002e, 0x002f, 0x002f,
    0x002f, 0x0030, 0x0030, 0x0030, 0x0031, 0x0031, 0x0031, 0x0032, 0x0032,
    0x0032, 0x0033, 0x0033, 0x0033, 0x0034, 0x0034, 0x0034, 0x0035, 0x0035,
    0x0035, 0x0035, 0x0036, 0x0036, 0x0036, 0x0037, 0x0037, 0x0037, 0x0038,
    0x0038, 0x0038, 0x0038, 0x0039, 0x0039, 0x0039, 0x0039, 0x003a, 0x003a,
    0x003a, 0x003b, 0x003b, 0x003b, 0x003b, 0x003c, 0x003c, 0x003c, 0x003c,
    0x003d, 0x003d, 0x003d, 0x003d, 0x003e, 0x003e, 0x003e, 0x003e, 0x003f,
    0x003f, 0x003f}

Lookuptable for sqrt(1 <= B < 2) sqrt_q15_tbl3[0] = 0; for (i = 0; i < 127; i++) { sqrt_q15_tbl3[i + 1] = (int)(sqrt((float)i + 1)

• sqrt(32768.0)) >> 5; }