How to get values of exponential functions in java and how to code the exponential functions

Question

I want to get value of an exponential function to my code, but I don't know how to code to exponential functions in Java. What is the way to code exponential functions in Java?

public class Demo {

    // inputs are declared
    private int x[] = {1, 0, 1, 0};
    //weights are declared
    private double w[] = {0.4, 0.6, 0.7, 0.8};
    private double temp = 0;

    private double z = 0;
    private int desiredOutput[] = {0, 1, 1, 1};

    private double sigmoidOutput[] = {1, 1, 1, 1};

    public void calculate() {
        for(int i =0; i < 4; i++) {
            temp = x[i] * w[i];
            z += temp;
        }
        /*
             I want to get the value of 1/(1+e to the power (-z) )
         */
    }

}

We can't do your homework for you. What you can do is show us what you have written so far, and what your understanding is. Then we can help you. — Kon, Jan 13 '16 at 17:12
Sorry, I asked this as I really don't know how to code exponential values in java. Here is my code — Kasun Siyambalapitiya, Jan 13 '16 at 17:19
Try this : http://www.tutorialspoint.com/java/number_exp.htm — Pritam Banerjee, Jan 13 '16 at 17:26
Thanks, this site is also about it: http://www.tutorialspoint.com/java/lang/math_exp.htm — Kasun Siyambalapitiya, Jan 13 '16 at 17:40

score 1 · Accepted Answer · answered Jan 13 '16 at 17:51

1

So you code should have this after whatever you have written in your calculate method.

Return the result from the calculate method or set result globally or however way you want to use it.

  double d = 1+ Math.exp(-z);
  double result = 1/d;

answered Jan 13 '16 at 17:51

Pritam Banerjee

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Thanksyou, I also found the answer on the above link – Kasun Siyambalapitiya Jan 13 '16 at 18:47
Can you please accept the answer so that it helps future readers. – Pritam Banerjee Jan 13 '16 at 18:54

score 0 · Answer 2 · edited Jan 13 '16 at 19:24

As according to the way mentioned here Math Exponential

import java.lang.Math;

public class Demo {
        // inputs are declared
        private int x[]={1,0,1,0};
        //weights are declared
        private double w[]={0.4,0.6,0.7,0.8};
        private double temp=0;

        private double z=0;
        private int desiredOutput[]={0,1,1,1};

        private double sigmoidOutput[]={1,1,1,1};

        public void calculate(){
            for(int i =0; i<4; i++){
                temp=x[i]*w[i];
                z+=temp;
            }
            /*
             * I want to get the value of 1/(1+e to the power (-z) )
             */
            double value=(1/(1+Math.exp(-z));
        }
}

How to get values of exponential functions in java and how to code the exponential functions

2 Answers2