在Objective C,XCode中定义一个类

Question

我是Objective C的新手,我正在尝试编写一个定义复数的类.代码似乎很好,但是当我打印到控制台时,我的实例变量值为0.

这是代码:

//
//  ComplexNumber.h
//  Mandelbrot Set
//
//  Created by Brett on 10-06-02.
//  Copyright 2010 __MyCompanyName__. All rights reserved.
//

#import <Foundation/Foundation.h>
#import <stdio.h>


@interface ComplexNumber : NSObject {

 double real;
 double imaginary;

}

// Getters
-(double) real;
-(double) imaginary;



// Setters
-(void)setReal: (double) a andImaginary: (double) b;

//Function
-(ComplexNumber *)squared;

@end


//
//  ComplexNumber.m
//  Mandelbrot Set
//
//  Created by Brett on 10-06-02.
//  Copyright 2010 __MyCompanyName__. All rights reserved.
//

#import "ComplexNumber.h"
#import <math.h>
#import <stdio.h>

@implementation ComplexNumber

-(double)real{
 return self->real;
}

-(double)imaginary{
 return self->imaginary;
}


-(void)setReal: (double) a andImaginary: (double) b{

 self->real=a;
 self->imaginary=b;

}

-(ComplexNumber *)squared{

 double a = pow(real,2);
 double b = pow(imaginary, 2);
 double c = 2*real*imaginary;

 ComplexNumber *d;
 [d setReal:(a-b) andImaginary: c];

 return d;
}

@end

在App Delegate中进行调试,我添加了:

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {   

 ComplexNumber *testNumber = [[ComplexNumber alloc] init];
 [testNumber setReal:55.0 andImaginary:30.0];
 NSLog(@"%d", testNumber.real);

    // Override point for customization after app launch    
    [window addSubview:viewController.view];
    [window makeKeyAndVisible];

 return YES;
}

但控制台每次都返回0.救命？

Answer 1

而不是%d,使用%f.D表示整数,F表示浮点("实数").