docs: public static double[][] diag(double[] vector){
  
  		// Note: According to the Java Language spec, an array is initialized with the default value, here 0.
  		double[][] diagonalMatrix = new double[vector.length][vector.length];
  
  		for(int index = 0; index < vector.length; index++) {
  			diagonalMatrix[index][index] = vector[index];
  		}
  
  		return diagonalMatrix;
  	}