code: @Nonnull
    @ReturnsMutableCopy
    public static float [] getConcatenated (final float aHead, @Nullable final float... aTailArray)
    {
      if (isEmpty (aTailArray))
        return new float [] { aHead };
  
      final float [] ret = new float [1 + aTailArray.length];
      ret[0] = aHead;
      System.arraycopy (aTailArray, 0, ret, 1, aTailArray.length);
      return ret;
    }
docs: Get a new array that combines the passed head element and the array. The
  head element will be the first element of the created array.
  
  @param aHead
  The first element of the result array.
  @param aTailArray
  The tail array. May be <code>null</code>.
  @return A non-<code>null</code> array with all elements in the correct
  order.