I'm developing a function that takes 3 parameters fctn (function, list, element) and you have to return a list with the intermediate states of the accumulator, as in the example below:
>>> fctn(lambda acc, x: acc + x, [1, 2, 3, 4], 0)
[0, 1, 3, 5,7]
My code:
def fctn(function, list, element):
acc = elem
for x in list:
list = map(lambda acc: lambda x: acc + x, l)
return list
But it does not return what I intend ...
See what you see:
import functools
# Utilizando Funcoes de alta ordem
def acumulator(n,dt):
current = n+dt['last']
dt['ac'].append(current)
dt['last'] = n
data = {'last': 0, 'ac': []}
list(map(lambda n: acumulator(n, data), [n for n in range(0,5)]))
print ('Acumuladores => ',data['ac'])
Acumuladores => [0, 1, 3, 5, 7]
According to the statement, I expected a different result: the list of partial cumulative sums.
Suggest a recursive definition:
def fctn(f,l,n):
if not l:
return [n]
else:
return [n]+fctn(f,l[1:], f(n,l[0]))
that is:
>>> fctn(lambda acc, x: acc + x, [1, 2, 3, 4], 0)
[0, 1, 3, 6, 10]