EN
Java - Math.cos() method example
0 points
The Math.cos() function returns the cosine of the specified angle in radians in the range -1 to +1.
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public class MathExample {2
3
public static void main(String[] args) {4
System.out.println( Math.cos( 0 ) ); // 1 <- 0 degrees5
System.out.println( Math.cos( 1.5707963267948966 ) ); // ~0 <- ~90 degrees == PI / 26
System.out.println( Math.cos( 3.1415926535897932 ) ); // ~-1 <- ~180 degrees == PI7
System.out.println( Math.cos( 4.71238898038469 ) ); // ~0 <- ~270 degrees == -PI * (3 / 2)8
System.out.println( Math.cos( 6.2831853071795850 ) ); // ~1 <- ~360 degrees == PI * 29
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System.out.println( Math.cos(-1.5707963267948966 ) ); // ~0 <- ~-90 degrees == -PI / 211
}12
}Note:
6.123233995736766e-17,-1.8369701987210297e-16and6.123233995736766e-17should be equal to0but they are not because of computation precision error.
| Syntax |
xxxxxxxxxx1 package java.lang;2 3 public final class Math {4 5 public static double cos(double number) { ... }6 7 }
|
| Parameters | number - double value in radians (primitive value). |
| Result |
returns a numeric value between |
| Description | cos is a static method that takes only one parameter and returns an approximation of cos(x) mathematical function result. |
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public class MathExample {2
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public static void main(String[] args) {4
double x1 = 0.0; // beginning of calculation in radians5
double x2 = Math.PI / 2; // ending of calculation radians6
7
double dx = Math.PI / 9; // calculation step in degrees8
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for (double rad = x1; rad <= x2; rad += dx) {10
double y = Math.cos(rad);11
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System.out.println("cos(" + rad + " rad) = " + y);13
}14
}15
}Output:
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cos(0.0 rad) = 1.02
cos(0.3490658503988659 rad) = 0.93969262078590843
cos(0.6981317007977318 rad) = 0.7660444431189784
cos(1.0471975511965976 rad) = 0.50000000000000015
cos(1.3962634015954636 rad) = 0.17364817766693041xxxxxxxxxx1
public class MathExample {2
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static double calculateCos(double deg) {4
double rad = (Math.PI / 180) * deg;5
6
return Math.cos(rad);7
}8
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public static void main(String[] args) {10
double x1 = 0.0; // beginning of calculation in degrees11
double x2 = 90.0; // ending of calculation degrees12
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double dx = 15.0; // calculation step in degrees14
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for (double deg = x1; deg <= x2; deg += dx) {16
double y = calculateCos(deg );17
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System.out.println("cos(" + deg + " deg) = " + y);19
}20
}21
}Output:
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cos(0.0 deg) = 1.02
cos(15.0 deg) = 0.96592582628906833
cos(30.0 deg) = 0.86602540378443874
cos(45.0 deg) = 0.70710678118654765
cos(60.0 deg) = 0.50000000000000016
cos(75.0 deg) = 0.258819045102520747
cos(90.0 deg) = 6.123233995736766E-17xxxxxxxxxx1
public class MathExample {2
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public static void main(String[] args) {4
double x1 = 0.0; // beginning of cosine chart5
double x2 = 3 * 3.14; // end of cosine chart6
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double dx = 3.14 / 4.0; // x axis step8
double dy = 1.0 / 5.0; // y axis step9
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for (double rad = x1; rad < x2; rad += dx) {11
double y1 = 0.0;12
double y2 = Math.cos(rad) + 1;13
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StringBuilder line = new StringBuilder();15
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for(double y = y1; y < y2; y += dy) {17
line.append(" ");18
}19
System.out.println(line.append("+"));20
}21
}22
}Output:
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+2
+3
+4
+5
+6
+7
+8
+9
+10
+11
+12
+