java.lang.Math.cos() method is used to find the trigonometric cosine of an angle of a double value in Java, (an angle must be in radians), for the given input (x – parameter).
Note: The computed result must be within 1 ulp of the exact result. Results must be semi-monotonic.
cos() method exists in Math class of java.lang package.Since: JDK1.0
Declaration of cos() Method
The declaration of cos() method is:
1 | public static double cos(double x) |
Syntax of cos() Method
The syntax of cos() method in Java is:
1 | java.lang.Math.cos(double x) |
Example for Syntax of cos() Method
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 | /* *Find the trigonometric cosine of an angle of given input(double) without importing the java.lang Package. */ public class JavaMathExample { public static void main(String[] args) { //Declaring variables double degree = 45; // convert given angle to radian double radians; radians = Math.toRadians(degree); double result; //Assign trigonometric cosine of an angle of radian to result variable result = java.lang.Math.cos(radians); //Printing result to the console System.out.println(result); } } |
Output:
0.7071067811865476
Another example for Syntax of cos() Method
By importing java.lang package the syntax of cos() method can be used as:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 | /* *Find the trigonometric cosine of an angle of given input(double) by importing the java.lang Package. */ import java.lang.*; //importing package public class JavaMathExample { public static void main(String[] args) { //Declaring variables double degree = 45; // convert given angle to radian double radians; radians = Math.toRadians(degree); double result; //Assign trigonometric cosine of an angle of radian to result variable result = Math.cos(radians); //Printing result to the console System.out.println(result); } } |
Output:
0.7071067811865476
Special Cases of cos() Method in Java
If the argument is NaN or an infinity, then the result is NaN.
Example
Output:
Example
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 | /* *This example shows some special cases of cos() method in Java */ import java.lang.*; //importing java.lang package public class JavaMathExample { public static void main(String[] args) { double positiveInfinity = Double.POSITIVE_INFINITY; double negativeInfinity = Double.NEGATIVE_INFINITY; double nan = Double.NaN; double result; //Here argument is positive infinity, output will also be NaN result = Math.cos(positiveInfinity); System.out.println(result); //Here argument is negative infinity, output will be NaN result = Math.cos(negativeInfinity); System.out.println(result); //Here argument is NaN, output will be NaN result = Math.cos(nan); System.out.println(result); } } |
Output:
NaN
NaN
NaN
Parameters of cos() Method in Java
x – Where x is any valid double input value. This parameter is required.
Error Handling
If the
If there is no argument (
Output:
x parameter is not a number cos() method returns an error.If there is no argument (
x – input value) passes to the method, the compiler will produce an error.Example1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 | /* *This example returns a compile time error */ import java.lang.*; //importing java.lang package public class JavaMathExample { public static void main(String[] args) { //Declaring variables String x = "Not a number"; double result; //argument is not a number result = Math.cos(x); System.out.println(result); //Here no argument is used result = Math.cos(); System.out.println(result); } } |
Output:
Error
Return Value of cos() Method in Java
cos() method returns the trigonometric cosine of an angle of a double value for the given input (x – parameter).
Java cos() Method Example 1
1 2 3 4 5 6 7 8 9 10 11 12 13 | import java.lang.*; //importing java.lang package public class JavaMathExample { public static void main(String[] args) { double value1 = Math.toRadians(Math.PI); double value2 = Math.toRadians(75); double value3 = Math.toRadians(0); System.out.println("The value of trigonometric cosine is: "+Math.cos( value1)); System.out.println("The value of trigonometric cosine is: "+Math.cos(value2)); System.out.println("The value of trigonometric cosine is: "+Math.cos(value3)); } } |
Output:
The value of trigonometric cosine is: 0.9984971498638638
The value of trigonometric cosine is: 0.25881904510252074
The value of trigonometric cosine is: 1.0
Java cos() Method Example 2
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 | import java.lang.*; //importing java.lang package public class JavaMathExample { public static void main(String[] args) { //Declare and initialize an array containing double values double test [] = { Math.PI,Math.E, Double.MIN_VALUE, Double.NaN, Double.MIN_EXPONENT, 42.867e-12, 16.852, 0, -2.58, -78.8569e7 }; //Use for loop to print trigonometric cosine of an angle of each element of the array for (int i = 0;i < test.length ; i++){ System.out.println( Math.cos(test[i]) ); } } } |
Output:
-1.0
-0.9117339147869651
1.0
NaN
-0.5550380793155483
1.0
-0.41392320157395335
1.0
-0.8464080412157756
-0.4202728158729685
