How to find the cumulative sum of numbers in a list?

Question

time_interval = [4, 6, 12]

I want to sum up the numbers like [4, 4+6, 4+6+12] in order to get the list t = [4, 10, 22].

Answer 1

Without having to use Numpy, you can loop directly over the array and accumulate the sum along the way. For example:

a=range(10)
i=1
while((i>0) & (i<10)):
    a[i]=a[i-1]+a[i]
    i=i+1
print a

Results in:

[0, 1, 3, 6, 10, 15, 21, 28, 36, 45]