input: Write a function to compute the running total of numbers in a given list using numpy. The function should return an array where each element is the cumulative sum of the elements up to the corresponding position in the input list. If the input list is empty, the function should return an empty array.
  
  import numpy as np
  
  def runningTotal(arr):
      return np.cumsum(arr)
  
  assert np.array_equal(runningTotal([1, 2, 3, 4]), np.array([1, 3, 6, 10])) == True
  assert np.array_equal(runningTotal([5, 4, 3, 2]), np.array([5, 9, 12, 14])) == True
  assert np.array_equal(runningTotal([]), np.array([])) == True
output: import numpy as np
  
  def runningTotal(arr):
      return np.cumsum(arr)