yey

.classpath

+<?xml version="1.0" encoding="UTF-8"?>
+<classpath>
+	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER"/>
+	<classpathentry kind="src" path=""/>
+	<classpathentry kind="output" path=""/>
+</classpath>

.gitignore

+/Complex.class
+/ComplexTest.class

.project

+<?xml version="1.0" encoding="UTF-8"?>
+<projectDescription>
+	<name>src</name>
+	<comment></comment>
+	<projects>
+	</projects>
+	<buildSpec>
+		<buildCommand>
+			<name>org.eclipse.jdt.core.javabuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+	</buildSpec>
+	<natures>
+		<nature>org.eclipse.jdt.core.javanature</nature>
+	</natures>
+</projectDescription>

Complex.java

+
+public class Complex {
+	double r;
+	double i;
+	
+	Complex(double r, double i){
+		this.r = r;
+		this.i = i;
+	}
+	Complex()
+	{
+		this.r = 0;
+		this.i = 0;
+	}
+	
+	double real()
+	{
+		return r;
+	}
+	double imag()
+	{
+		return i;
+	}
+	double magnitude()
+	{
+		return Math.sqrt(r*r + i*i);
+	}
+	double argument()
+	{
+		return Math.atan2(i, r);
+	}
+	Complex add(Complex nr)
+	{
+		Complex sum = new Complex();
+		sum.i = this.i + nr.i;
+		sum.r = this.r + nr.r;
+		return sum;
+	}
+
+}

ComplexTest.java

+import static org.junit.jupiter.api.Assertions.*;
+
+import org.junit.jupiter.api.Test;
+
+class ComplexTest {
+
+    @Test
+    void testBasic() {
+        /* Constructor should put the first parameter as the real part and second as the imaginary part.
+         * real() should return real part, imag() imaginary part.
+         */
+        Complex a = new Complex(4.2, 5.7);
+        assertEquals(4.2, a.real(), 1e-6);
+        assertEquals(5.7, a.imag(), 1e-6);
+        Complex b = new Complex();
+        assertEquals(0, b.real(), 1e-6);
+        assertEquals(0, b.imag(), 1e-6);
+    }
+    
+    @Test
+    void testMagnitude() {
+        /* magnitude() should return the magnitude of the complex number */
+        Complex a = new Complex(9.6, 11.5);
+        assertEquals(14.98032042, a.magnitude(), 1e-6);
+    }
+    
+    @Test
+    void testArgument() {
+        /* argument() should return the argument of the complex number */
+        Complex a = new Complex(9.6, 11.5);
+        assertEquals(0.87520335, a.argument(), 1e-6);
+    }
+    
+    @Test
+    void testAdd() {
+        /* add() should return a new complex number which is the sum of this and the parameter */
+        Complex a = new Complex(6.6, 12.9);
+        Complex b = new Complex(13.1, 13.5);
+        Complex c = a.add(b);
+        assertEquals(19.7, c.real(), 1e-6);
+        assertEquals(26.4, c.imag(), 1e-6);
+    }
+    
+    @Test
+    void testToString() {
+        /* toString() should return a string like 1.2 + j3.4 where 1.2 is the real part
+         * and 3.4 the imaginary part.
+         *
+        Complex a = new Complex(1.2, 3.4);
+        assertEquals("1.2 + j3.4", a.toString());
+        Complex b = new Complex(1.2, 0.0);
+        assertEquals("1.2", b.toString());
+        Complex c = new Complex(0.0, 9.3);
+        assertEquals("j9.3", c.toString());
+        Complex d = new Complex(1.2, -3.4);
+        assertEquals("1.2 - j3.4", d.toString());*/
+    }
+}
+