OPI_LR2011_ch3

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class Automobile {

private static int number; Automobile(){

number++;

System.out.println("From Automobile constructor:"+ " number = "+number);

} }

public class AutomobiieTest{

public static void main(String[] args){

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3.2.8 7 Complex

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class Complex {

private static final double EPS = le-12; // .2]789:; 2<]/9gO7; private double re, im; // ?8>97= > R7/R= ]=9:/7=

// ˆ2:/4/ P279:4NP:24/

Complex(double re, double im) { this, re = re; this.im = im;

}

Complex(double re){this(re, 0.0); } Complex(){this(0.0, 0.0); } Complex(Complex z){this(z.re, z.im) ; }

// hO:26/ 629:N0N

public double getRe(){return re;} public double getlmf){return im;}

public Complex get(){return new Complex(re, im);} public void setRe(double re){this.re = re;} public void setlm(double im){this.im = im;} public void set(Complex z){re = z.re; im = z.im;}

// h26Ng; 8 =4\NRO7: P2R0gOP972\2 ]/9g=

public double mod(){return Math.sqrt(re * re + im * im);} public double arg()(return Math.atan2(re, im);}

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public boolean isReal(){return Math.abs(im) < EPS;} public void pr(){ // i/@86 7= OP4=7

System.out.println(re +(im < 0.0 ? "": '"+") + im + "i");

}

//•O4O@/37=]O775 RO:268@ Pg=9N Object public boolean equals(Complex z){

return Math.abs(re -'z.re) < EPS && Math.abs(im - z.im) < EPS;

}

public String toString(){

return "Complex: " + re + " " + im;

}

//hO:26/, j2 4O=g83Nn:; 20O4=_8ƒ +=, -=, *=, /= public void add(Complex z){re += z.re; im += z.im;} public void sub(Complex z){re -= z.re; im -= z.im;} public void mul(Complex z){

double t = re * z.re - im * z. im; im = re * z.im + im * z.re; re = t;

}

public void div(Complex z){ double m = z.mod();

double t = re * z.re - im * z.im; im =(im * z.re - re * z.im) / m;

44

re = t / m;

}

// hO:26/, j2 4O=g83Nn:; 20O4=_8ƒ +, -, *, / public Complex plus(Complex z){

return new Complex(re + z.re, im + z im);

}

public Complex minus(Complex z){

return new Complex(re - z.re, im - z.im);

}

public Complex asterisk(Complex z){ return new Complex(

re * z.re - im * z.im, re * z.im + im * z re);

}

public Complex slash(Complex z){ double m = z.mod();

return new Complex(

(re * z.re - im * z.im) / m,(im * z.re - re * z.im) / m);

}

}

// •O4O@84/R2 42<2:N Pg=9N Complex public class ComplexTest{

public static void main(Stringf] args){ Complex zl = new Complex(),

z2 = new Complex(1.5),

z3 = new Complex(3.6, -2.2),

z4 = new Complex(z3);

System.out.printlnf); // a=g/f=bR2 0242^78> 4562P System.out.print("zl = "); zl.pr(); System.out.print("z2 = "); z2.pr(); System.out.print("z3 = "); z3.pr(); System.out.print("z4 = "}; z4.pr();

System.out.print("z2 + z3 = "}; z2.pr(); z2.div(z3);

System.out.print("z2 / z3 = "); z2.pr(); z2 = z2.plus(z2);

System.out.print("z2 + z2 = "); z2.pr(); z3 = z2.slash(zl);

System.out.print("z2 / zl = "); z3.pr();

}

}

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