CMSIS DSP Software Library: arm_linear_interp_example_f32.c Main Page Modules Data Structures Files Examples arm_linear_interp_example_f32.c /* ---------------------------------------------------------------------- * Copyright (C) 2010 ARM Limited. All rights reserved. * * $Date: 29. November 2010 * $Revision: V1.0.3 * * Project: CMSIS DSP Library * Title: arm_linear_interp_example_f32.c * * Description: Example code demonstrating usage of sin function * and uses linear interpolation to get higher precision * * Target Processor: Cortex-M4/Cortex-M3 * * * Version 1.0.3 2010/11/29 * Re-organized the CMSIS folders and updated documentation. * * Version 1.0.1 2010/10/05 KK * Production release and review comments incorporated. * * Version 1.0.0 2010/09/20 KK * Production release and review comments incorporated. * ------------------------------------------------------------------- */ #include "arm_math.h" #include "math_helper.h" #define SNR_THRESHOLD 90 #define TEST_LENGTH_SAMPLES 10 #define XSPACING (0.00005f) /* ---------------------------------------------------------------------- * Test input data for F32 SIN function * Generated by the MATLAB rand() function * randn('state', 0) * xi = (((1/4.18318581819710)* randn(blockSize, 1) * 2* pi)); * --------------------------------------------------------------------*/ float32_t testInputSin_f32[TEST_LENGTH_SAMPLES] = { -0.649716504673081170, -2.501723745497831200, 0.188250329003310100, 0.432092748487532540, -1.722010988459680800, 1.788766476323060600, 1.786136060975809500, -0.056525543169408797, 0.491596272728153760, 0.262309671126153390 }; /*------------------------------------------------------------------------------ * Reference out of SIN F32 function for Block Size = 10 * Calculated from sin(testInputSin_f32) *------------------------------------------------------------------------------*/ float32_t testRefSinOutput32_f32[TEST_LENGTH_SAMPLES] = { -0.604960695383043530, -0.597090287967934840, 0.187140422442966500, 0.418772124875992690, -0.988588831792106880, 0.976338412038794010, 0.976903856413481100, -0.056495446835214236, 0.472033731854734240, 0.259311907228582830 }; /*------------------------------------------------------------------------------ * Method 1: Test out Buffer Calculated from Cubic Interpolation *------------------------------------------------------------------------------*/ float32_t testOutput[TEST_LENGTH_SAMPLES]; /*------------------------------------------------------------------------------ * Method 2: Test out buffer Calculated from Linear Interpolation *------------------------------------------------------------------------------*/ float32_t testLinIntOutput[TEST_LENGTH_SAMPLES]; /*------------------------------------------------------------------------------ * External table used for linear interpolation *------------------------------------------------------------------------------*/ extern float32_t arm_linear_interep_table[188495]; /* ---------------------------------------------------------------------- * Global Variables for caluclating SNR's for Method1 & Method 2 * ------------------------------------------------------------------- */ float32_t snr1; float32_t snr2; /* ---------------------------------------------------------------------------- * Calculation of Sine values from Cubic Interpolation and Linear interpolation * ---------------------------------------------------------------------------- */ int32_t main(void) { uint32_t i; arm_status status; arm_linear_interp_instance_f32 S = {188495, -3.141592653589793238, XSPACING, &arm_linear_interep_table[0]}; /*------------------------------------------------------------------------------ * Method 1: Test out Calculated from Cubic Interpolation *------------------------------------------------------------------------------*/ for(i=0; i< TEST_LENGTH_SAMPLES; i++) { testOutput[i] = arm_sin_f32(testInputSin_f32[i]); } /*------------------------------------------------------------------------------ * Method 2: Test out Calculated from Cubic Interpolation and Linear interpolation *------------------------------------------------------------------------------*/ for(i=0; i< TEST_LENGTH_SAMPLES; i++) { testLinIntOutput[i] = arm_linear_interp_f32(&S, testInputSin_f32[i]); } /*------------------------------------------------------------------------------ * SNR calculation for method 1 *------------------------------------------------------------------------------*/ snr1 = arm_snr_f32(testRefSinOutput32_f32, testOutput, 2); /*------------------------------------------------------------------------------ * SNR calculation for method 2 *------------------------------------------------------------------------------*/ snr2 = arm_snr_f32(testRefSinOutput32_f32, testLinIntOutput, 2); /*------------------------------------------------------------------------------ * Initialise status depending on SNR calculations *------------------------------------------------------------------------------*/ if( snr2 > snr1) { status = ARM_MATH_SUCCESS; } else { status = ARM_MATH_TEST_FAILURE; } /* ---------------------------------------------------------------------- ** Loop here if the signals fail the PASS check. ** This denotes a test failure ** ------------------------------------------------------------------- */ if( status != ARM_MATH_SUCCESS) { while(1); } }  All Data Structures Files Functions Variables Typedefs Enumerations Enumerator Defines Generated on Mon Nov 29 2010 17:19:55 for CMSIS DSP Software Library by  1.7.2