Added sqrt method

README.md

@@ -4,11 +4,11 @@
 A library which implements the complex number data type in Java. 
 
 The features of this library include:  
-1- Arithmetic Operations (addition, subtraction, multiplication, division)  
-2- Complex Specific Operations - Conjugate, Inverse, Absolute/Magnitude, Argument/Phase  
-3- Trigonometric Operations - sin, cos, tan, cot, sec, cosec  
-4- Mathematical Functions - exp  
-5- **Complex Parsing** of type x+yi  
+* Arithmetic Operations (addition, subtraction, multiplication, division)
+* Complex Specific Operations - Conjugate, Inverse, Absolute/Magnitude, Argument/Phase  
+* Trigonometric Operations - sin, cos, tan, cot, sec, cosec  
+* Mathematical Functions - exp, square, sqrt
+* **Complex Parsing** of type x+yi  
 
 
 ### Example Usage  
@@ -55,6 +55,11 @@ public class TestComplexNumber
 		// sin, cos
 		System.out.println(ComplexNumber.sin(c3).toString());
 		System.out.println(ComplexNumber.cos(c3).toString());
+
+		// square and square root
+		ComplexNumber c4 = new ComplexNumber(-5, 12);
+		System.out.println(c4.square());
+		System.out.println(c4.sqrt());
 
 	}
 }

TestComplexNumber.java

@@ -39,6 +39,11 @@ public static void main(String args[])
 		// sin, cos
 		System.out.println(ComplexNumber.sin(c3).toString());
 		System.out.println(ComplexNumber.cos(c3).toString());
+
+		// square and square root
+		ComplexNumber c4 = new ComplexNumber(-5, 12);
+		System.out.println(c4.square());
+		System.out.println(c4.sqrt());
 
 	}
 }

com/abdulfatir/jcomplexnumber/ComplexNumber.java

@@ -181,6 +181,20 @@ public ComplexNumber square()
 		double _imaginary = 2*this.real*this.imaginary;
 		return new ComplexNumber(_real,_imaginary);
 	}
+
+	/**
+	 * The square root of the current complex number.
+	 * @return a <code>ComplexNumber</code> which is the square root of the current complex number.
+	 */
+
+	public ComplexNumber sqrt()
+	{
+		double r = Math.sqrt(this.real*this.real + this.imaginary*this.imaginary);
+		double real = Math.sqrt((r + this.real) / 2);
+		double imaginary = Math.sqrt((r - this.real) / 2);
+		return new ComplexNumber(real, imaginary);
+	}
+
 	/**
 	* @return the complex number in x + yi format
 	*/