package PEU.P.wave;
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public class Laplasian{
  @SuppressWarnings("unused")
  public double[] laplasian1d(double[] input, double scale ) {
    double [] output = new double [input.length];
    double []lap=new double[5];
    double sig = scale; //default 1.6
    double t = 0;
    double sumhere = 0;
    lap[0]=0;
    lap[1]=-3;
    lap[2]=scale;//default=7
    lap[3]=-3;
    lap[4]=0;
    for(int l = 0; l<5; ++l){          
      sumhere = sumhere + lap[l];
    }     
    //   System.out.println("--->"+sumhere);  
    //--normalization      
    double sum1=0;
    for(int j=0; j<5; ++j){
      lap[j] = lap[j]/sumhere;
      sum1 = sum1 + lap[j];
    }  
    //--end of producing gaussian matrix
    // System.out.println("gaussian sum: " + sum1);
    double sum=0;
    for(int i=2;i<input.length-2;i++){  
      sum=0;
      for(int j=-2;j<3;j++){
        sum = sum + (input[i+j]* lap[j+2]);  
      }
      output[i]=sum;
    }
    return output;
  };
}