From f3dc2dc2ad43ff4364e60f7803edb612dc99c758 Mon Sep 17 00:00:00 2001 From: James Cotton Date: Fri, 3 Aug 2012 12:31:15 -0500 Subject: [PATCH] Store 180 deg in flash now and even make the flash and ram version share a lookup method. Still don't get the same results. --- flight/Libraries/math/sin_lookup.c | 66 +++++++++++++----------------- 1 file changed, 28 insertions(+), 38 deletions(-) diff --git a/flight/Libraries/math/sin_lookup.c b/flight/Libraries/math/sin_lookup.c index 2a5508fce..a536f3f34 100644 --- a/flight/Libraries/math/sin_lookup.c +++ b/flight/Libraries/math/sin_lookup.c @@ -33,6 +33,7 @@ #include "stdbool.h" #include "stdint.h" +//#define FLASH_TABLE #ifdef FLASH_TABLE /** Version of the code which precomputes the lookup table in flash **/ @@ -46,7 +47,16 @@ 0.766044f,0.777146f,0.788011f,0.798636f,0.809017f,0.819152f,0.829038f,0.838671f,0.848048f,0.857167f, 0.866025f,0.874620f,0.882948f,0.891007f,0.898794f,0.906308f,0.913545f,0.920505f,0.927184f,0.933580f, 0.939693f,0.945519f,0.951057f,0.956305f,0.961262f,0.965926f,0.970296f,0.974370f,0.978148f,0.981627f, - 0.984808f,0.987688f,0.990268f,0.992546f,0.994522f,0.996195f,0.997564f,0.998630f,0.999391f,0.999848f + 0.984808f,0.987688f,0.990268f,0.992546f,0.994522f,0.996195f,0.997564f,0.998630f,0.999391f,0.999848f, + 1.000000f,0.999848f,0.999391f,0.998630f,0.997564f,0.996195f,0.994522f,0.992546f,0.990268f,0.987688f, + 0.984808f,0.981627f,0.978148f,0.974370f,0.970296f,0.965926f,0.961262f,0.956305f,0.951057f,0.945519f, + 0.939693f,0.933580f,0.927184f,0.920505f,0.913545f,0.906308f,0.898794f,0.891007f,0.882948f,0.874620f, + 0.866025f,0.857167f,0.848048f,0.838671f,0.829038f,0.819152f,0.809017f,0.798636f,0.788011f,0.777146f, + 0.766044f,0.754710f,0.743145f,0.731354f,0.719340f,0.707107f,0.694658f,0.681998f,0.669131f,0.656059f, + 0.642788f,0.629320f,0.615661f,0.601815f,0.587785f,0.573576f,0.559193f,0.544639f,0.529919f,0.515038f, + 0.500000f,0.484810f,0.469472f,0.453990f,0.438371f,0.422618f,0.406737f,0.390731f,0.374607f,0.358368f, + 0.342020f,0.325568f,0.309017f,0.292372f,0.275637f,0.258819f,0.241922f,0.224951f,0.207912f,0.190809f, + 0.173648f,0.156434f,0.139173f,0.121869f,0.104528f,0.087156f,0.069756f,0.052336f,0.034899f,0.017452f }; int sin_lookup_initalize() @@ -54,28 +64,6 @@ int sin_lookup_initalize() return 0; } -/** - * Use the lookup table to return sine(angle) where angle is in radians - * to save flash this cheats and uses trig functions to only save - * 90 values - * @param[in] angle Angle in degrees - * @returns sin(angle) -*/ -float sin_lookup_deg(float angle) -{ - int i_ang = ((int32_t) angle) % 360; - if(i_ang > 270) // for 270 to 360 deg - return -sin_table[360 - i_ang]; - else if (i_ang > 180) // for 180 to 270 deg - return -sin_table[i_ang - 180]; - else if (i_ang > 90) // for 90 to 170 deg - return sin_table[180 - i_ang]; - else // for 0 to 90 deg - return sin_table[i_ang]; - - return 0; -} - #else /** Version of the code which allocates the lookup table in heap **/ @@ -98,23 +86,25 @@ int sin_lookup_initalize() return 0; } - - -/** - * Uses the lookup table to calculate sine (angle is in degrees) - * @param[in] angle in degrees - * @returns sin(angle) - */ -float sin_lookup_deg(float angle) { - int i_ang = ((int32_t)angle) % 360; - if (i_ang > 180) - return - sin_table[i_ang-180]; - else - return sin_table[i_ang]; -} - #endif +/** + * Use the lookup table to return sine(angle) where angle is in radians + * to save flash this cheats and uses trig functions to only save + * 90 values + * @param[in] angle Angle in degrees + * @returns sin(angle) +*/ +float sin_lookup_deg(float angle) +{ + int i_ang = ((int32_t) angle) % 360; + if (i_ang > 180) // for 180 to 270 deg + return -sin_table[i_ang - 180]; + else // for 0 to 90 deg + return sin_table[i_ang]; + + return 0; +} /** * Get cos(angle) using the sine lookup table