Program: 108187
Project: 108187
Buggy source:
/** 
 * The method for computing the first derivatives of the object functions evaluated at the iterated solutions.
 * @param iteratedSolution The iterated vector of solutions.
 * @return The first derivatives of the object functions evaluated at theiterated solutions.
 */
@Override protected double[][] firstDerivativeMatrix(final double[] iteratedSolution){
  final double a=iteratedSolution[0];
  final double b=iteratedSolution[1];
  final double[][] result=new double[iteratedSolution.length][iteratedSolution.length];
  final double val0=(b - 1d) * (f - 1d);
  final double val1=val0 - 1d;
  final double val2=1d - val0;
  final double val3=a * val0 / val1 - 1d;
  final double val4=Math.pow(-b / val1,a);
  final double val5=val0 + 2d;
  final double val6=Math.pow(f,2d);
  final double val7=Math.pow(b,a);
  final double val8=val7 * val6 * k;
  final double val9=a * val8;
  final double val10=2d * Math.pow(val2,a + 2d);
  final double val11=Math.pow((val1),2d);
  final double val12=(a - 1d) * val5;
  final double val13=f * k;
  final double val14=f - 1d;
  final double val15=a - 1d;
  final double val16=b - 1d;
  final double val17=val12 * val16;
  result[0][0]=-val13 * Math.log(-b / val1) * val3* val4 - (val13 * val4 * val0) / val1;
  result[0][1]=a * val13 * (1d / val1 - (b * val14) / val11)* val3* Math.pow((-b / val1),val15) - val13 * val4 * ((a * val14) / val1 - (a * val16 * Math.pow(val14,2d)) / val11);
  result[1][0]=(val9 * Math.log(val2) * val17) / val10 - (val9 * Math.pow(val16,2d) * val14) / val10 - (val8 * val17) / val10 - (val9 * Math.log(b) * val17) / val10;
  result[1][1]=-(val9 * val12) / val10 - (Math.pow(a,2d) * Math.pow(b,val15) * val6* k* val17) / val10 - (val9 * val15 * val0) / val10 - (val9 * val12 * (a + 2d)* val0) / (2d * Math.pow(val2,(a + 3d)));
  return result;
}

Fixed version (ground truth):
/** 
 * The method for computing the first derivatives of the object functions evaluated at the iterated solutions.
 * @param iteratedSolution The iterated vector of solutions.
 * @return The first derivatives of the object functions evaluated at theiterated solutions.
 */
@Override protected double[][] firstDerivativeMatrix(final double[] iteratedSolution){
  final double a=iteratedSolution[0];
  final double b=iteratedSolution[1];
  final double[][] result=new double[iteratedSolution.length][iteratedSolution.length];
  final double val0=(b - 1d) * (f - 1d);
  final double val1=val0 - 1d;
  final double val2=1d - val0;
  final double val3=a * val0 / val1 - 1d;
  final double val4=Math.pow(-b / val1,a);
  final double val6=Math.pow(f,2d);
  final double val7=Math.pow(b,a);
  final double val8=val7 * val6 * k;
  final double val9=a * val8;
  final double val10=2d * Math.pow(val2,a + 2d);
  final double val11=Math.pow((val1),2d);
  final double val13=f * k;
  final double val14=f - 1d;
  final double val15=a - 1d;
  final double val16=b - 1d;
  final double val17=val15 * val0;
  final double val18=val6 * k;
  final double val19=(val17 + 2d);
  final double val20=val18 * val19;
  result[0][0]=-val13 * Math.log(-b / val1) * val3* val4 - (val13 * val4 * val0) / val1;
  result[0][1]=a * val13 * (1d / val1 - (b * val14) / val11)* val3* Math.pow((-b / val1),val15) - val13 * val4 * ((a * val14) / val1 - (a * val16 * Math.pow(val14,2d)) / val11);
  result[1][0]=(val9 * Math.log(val2) * val19* val16) / (val10) - (val9 * Math.pow(val16,2d) * val14) / (val10) - (val7 * val20 * val16) / (val10) - (a * val7 * val18* Math.log(b)* val19* val16) / (val10);
  result[1][1]=-(val9 * val19) / (val10) - (Math.pow(a,2d) * Math.pow(b,val15) * val20* val16) / val10 - (a * val7 * val18* val17) / val10 - (a * val7 * val20* (a + 2d)* val0) / (2d * Math.pow((val2),(a + 3d)));
  return result;
}