Merge pull request #198 from SunYatong/2.0.0

modify softmax function for mathematical robustness.
guoguibing · Oct 8, 2017 · 38d81ad · 38d81ad
2 parents 7c22c99 a520e67
commit 38d81ad
Showing 1 changed file with 10 additions and 5 deletions.
diff --git a/core/src/main/java/net/librec/math/algorithm/Maths.java b/core/src/main/java/net/librec/math/algorithm/Maths.java
@@ -141,16 141,21 @@ protected double gaussian(double x, double mu, double sigma) {
  }
 
  /**
- * logistic function g(x)
  * softmax function
  *
- * @param x given parameter x
- * @return value of logistic function g(x)
- * @throws Exception  if error occurs
  * @param x given array
  * @return output array of softmax function
  * @throws Exception if error occurs
  */
  public static double[] softmax(double[] x) throws Exception {
  double[] expx = new double[x.length];
 
  double max = x[0];
  for(int i=1;i<x.length;i )
  max = Math.max(x[i],max);
 
  for (int i = 0; i < x.length; i ) {
- expx[i] = Math.exp(x[i]);
  expx[i] = Math.exp(x[i] - max);
  }
  return norm(expx);
  }