40 lines
1.6 KiB
Java
40 lines
1.6 KiB
Java
package Maths;
|
|
|
|
/**
|
|
* <p>
|
|
* In mathematics, an arithmetic progression (AP) or arithmetic sequence is a sequence of numbers such that the
|
|
* difference between the consecutive terms is constant. Difference here means the second minus the first.
|
|
* For instance, the sequence 5, 7, 9, 11, 13, 15, . . . is an arithmetic progression with common difference of 2.
|
|
* <p>
|
|
* Wikipedia: https://en.wikipedia.org/wiki/Arithmetic_progression
|
|
*/
|
|
public class SumOfArithmeticSeries {
|
|
public static void main(String[] args) {
|
|
|
|
/* 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10 */
|
|
assert Double.compare(55.0, sumOfSeries(1, 1, 10)) == 0;
|
|
|
|
/* 1 + 3 + 5 + 7 + 9 + 11 + 13 + 15 + 17 + 19 */
|
|
assert Double.compare(100.0, sumOfSeries(1, 2, 10)) == 0;
|
|
|
|
/* 1 + 11 + 21 + 31 + 41 + 51 + 61 + 71 + 81 + 91 */
|
|
assert Double.compare(460.0, sumOfSeries(1, 10, 10)) == 0;
|
|
|
|
/* 0.1 + 0.2 + 0.3 + 0.4 + 0.5 + 0.6 + 0.7 + 0.8 + 0.9 + 1.0 */
|
|
assert Double.compare(5.5, sumOfSeries(0.1, 0.1, 10)) == 0;
|
|
|
|
assert Double.compare(49600.0, sumOfSeries(1, 10, 100)) == 0;
|
|
}
|
|
|
|
/**
|
|
* Calculate sum of arithmetic series
|
|
*
|
|
* @param firstTerm the initial term of an arithmetic series
|
|
* @param commonDiff the common difference of an arithmetic series
|
|
* @param numOfTerms the total terms of an arithmetic series
|
|
* @return sum of given arithmetic series
|
|
*/
|
|
private static double sumOfSeries(double firstTerm, double commonDiff, int numOfTerms) {
|
|
return numOfTerms / 2.0 * (2 * firstTerm + (numOfTerms - 1) * commonDiff);
|
|
}
|
|
} |