why can't I filter a list based on an itertools condition using dropwhile?
This is the docs and the example.
https://docs.python.org/3/library/itertools.html#itertools.dropwhile
def less_than_10(x):
return x < 10
itertools.takewhile(less_than_10, itertools.count()) =>
0, 1, 2, 3, 4, 5, 6, 7, 8, 9
so I have a list I have created (converted from itertools). pm is permutations
print(stats)
[(1, 2, 3), (1, 2, 4), (1, 2, 5), (1, 3, 2), (1, 3, 4), (1, 3, 5), (1, 4, 2),
(1, 4, 3), (1, 4, 5), (1, 5, 2), (1, 5, 3), (1, 5, 4), (2, 1, 3), (2, 1, 4),
(2, 1, 5), (2, 3, 1), (2, 3, 4), (2, 3, 5), (2, 4, 1), (2, 4, 3), (2, 4, 5),
(2, 5, 1), (2, 5, 3), (2, 5, 4), (3, 1, 2), (3, 1, 4), (3, 1, 5), (3, 2, 1),
(3, 2, 4), (3, 2, 5), (3, 4, 1), (3, 4, 2), (3, 4, 5), (3, 5, 1), (3, 5, 2),
(3, 5, 4), (4, 1, 2), (4, 1, 3), (4, 1, 5), (4, 2, 1), (4, 2, 3), (4, 2, 5),
(4, 3, 1), (4, 3, 2), (4, 3, 5), (4, 5, 1), (4, 5, 2), (4, 5, 3), (5, 1, 2),
(5, 1, 3), (5, 1, 4), (5, 2, 1), (5, 2, 3), (5, 2, 4), (5, 3, 1), (5, 3, 2),
(5, 3, 4), (5, 4, 1), (5, 4, 2), (5, 4, 3)]
I simply wanted to create an easy way to create summary stats of my stats
list(poorly named). So in this case easy to check answers. so how many tuples
in my list have a 1 in item[0] and how many don't. Then hoping to build on that
for example how many have item[0] == 1 && (item[1] == 2 or item[1] == 4) etc.
I can achieve it via an else if but that would become ugly quick.
for item in stats:
if item[0] == 1:
nums += 1
elif item[0] != 1:
not_in += 1
else:
pass
myString = "i have {a} in and {b} so the percentage is {c}%".format(a=nums,
b=not_in, c=(nums/(nums + not_in)))
I thought dropwhile from the docs appeared a good option but it returns bool.
answer = listb.extend(itertools.dropwhile(item[0] != 1, stats))
---------------------------------------------------------------------------
TypeError Traceback (most recent call last)
<ipython-input-130-70c93104d1c5> in <module>()
----> 1 answer = listb.extend(itertools.dropwhile(item[0] != 1, stats))
TypeError: 'bool' object is not callable
Think I am making this hard somewhere that it is actually easy.
As an aside do I really need to convert the iterator object to a list to create
and summarize iterator contents?
Currently I have created a function to achieve this as below.
def myGen(parcel):
x = []
[x.append(y) for y in parcel]
return x
myPerm = pm(range(1,6),3)
stats = myGen(myPerm)
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