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java programming incorrect answeri have to write a program that gives the summation of 1/i for any given i. i came up with the following program but for some reason it always provides the answer 1.0, can someone tell me what is wrong here? import java.util.Scanner; class Series{ Scanner sc = new Scanner(System.in); double series(int i){ if (i==1) return 1; else return 1/(i*i) + series(i-1); } public void demo(){ int i; System.out.println("Provide a number to compute the series for"); i = sc.nextInt(); System.out.println("series of " + i + " is " + series(i)); } public static void main(String[] args) { new Series().demo(); } } |

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If i = 2, what d'hell is "summed"? Please provide an example. Your post is "obscure"...or do I need another coffee? :confused: |

Assuming $\displaystyle i$ is a variable and not the imaginary unit: $\displaystyle \sum_{i=0}^\infty \frac{\alpha}i = \infty \thinspace \text{if} \thinspace \alpha\ne{0} \thinspace \wedge \thinspace i\ne{0}$ This can be proven with the harmonic series test. So what do you mean exactly? If you mean just $\displaystyle \frac{1}i$ you can use $\displaystyle i^{-1}$ |

I believe the OP's program is supposed to find: $\displaystyle S_i=\sum_{k=1}^{i}\left(\frac{1}{k}\right)$ It looks to me though, the algorithm coded would provide: $\displaystyle S_i=\sum_{k=1}^{i}\left(\frac{1}{k^2}\right)$ However, I'm not a Java programmer. :D |

Your only error is in method series. You said i is an int, so 1/i*i is 0 for any i>1! So just change 1/i*i to 1.0/i*i.By the way I am surprised that your program runs as given. I thought main had to be within a public class? |

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