python - Cumulative Sum of a list of numbers -

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• how find cumulative sum of numbers in list? 15 answers

i have checked other questions similar none of them seem answer problem. need write function returns cumulative sum of list of number. have doesn't seem work properly:

numbers = [4,3,6]  sums = []  def cumulativesum(numbers):     in range(len(numbers) - 1):        sums.append(numbers[i] + numbers[i + 1])     return sums  print cumulativesum(numbers)       ##[4, 7, 13] answers should come out 

this work, never accessing sum array, need in order increment values calculated , put

numbers = [4,3,6]  sums = []  def cumulativesum(numbers):     sums.append(numbers[0])     in range(len(numbers) - 1):         if == 0:             sums.append(numbers[i] + numbers[i + 1])         else:             sums.append(numbers[i + 1] + sums[i])     return sums  print cumulativesum(numbers)