gistfile1.m

// test3 = 0.922481 atan2f float
// test4 = 1.067147 atan2f double
// test2 = 2.844713 atan2 double
// test1 = 3.252539 atan2 float

#import "Atan2TestAppDelegate.h"

#define COUNT (1000000)

@implementation Atan2TestAppDelegate

@synthesize window;

void test1(float* array1, float* array2, float* array3){
	for(int i = 0; i < COUNT; i++){
		array3[i] = atan2(array1[i], array2[i]);
	}
}

void test2(double* array1, double* array2, double* array3){
	for(int i = 0; i < COUNT; i++){
		array3[i] = atan2(array1[i], array2[i]);
	}
}

void test3(float* array1, float* array2, float* array3){
	for(int i = 0; i < COUNT; i++){
		array3[i] = atan2f(array1[i], array2[i]);
	}
}

void test4(double* array1, double* array2, double* array3){
	for(int i = 0; i < COUNT; i++){
		array3[i] = atan2f(array1[i], array2[i]);
	}
}

- (void)applicationDidFinishLaunching:(UIApplication *)application {    

    // Override point for customization after application launch
    [window makeKeyAndVisible];
	
	float* arrayf1 = malloc(sizeof(float)*COUNT);
	float* arrayf2 = malloc(sizeof(float)*COUNT);
	float* arrayf3 = malloc(sizeof(float)*COUNT);
	double* arrayd1 = malloc(sizeof(double)*COUNT);
	double* arrayd2 = malloc(sizeof(double)*COUNT);
	double* arrayd3 = malloc(sizeof(double)*COUNT);
	
	for(int i = 0; i < COUNT; i++){
		arrayf1[i] = random();
		arrayf2[i] = random();
		arrayd1[i] = random();
		arrayd2[i] = random();
	}
	
	NSDate* a_dateStart1 = [NSDate date];
	test1(arrayf1, arrayf2, arrayf3);
	NSLog(@"%s test1 = %f", __func__, [[NSDate date] timeIntervalSinceDate:a_dateStart1]);
	
	NSDate* a_dateStart2 = [NSDate date];
	test2(arrayd1, arrayd2, arrayd3);
	NSLog(@"%s test2 = %f", __func__, [[NSDate date] timeIntervalSinceDate:a_dateStart2]);

	NSDate* a_dateStart3 = [NSDate date];
	test3(arrayf1, arrayf2, arrayf3);
	NSLog(@"%s test3 = %f", __func__, [[NSDate date] timeIntervalSinceDate:a_dateStart3]);
	
	NSDate* a_dateStart4 = [NSDate date];
	test4(arrayd1, arrayd2, arrayd3);
	NSLog(@"%s test4 = %f", __func__, [[NSDate date] timeIntervalSinceDate:a_dateStart4]);
	
	free(arrayf1);
	free(arrayf2);
	free(arrayf3);
	free(arrayd1);
	free(arrayd2);
	free(arrayd3);
}


- (void)dealloc {
    [window release];
    [super dealloc];
}


@end