list_of_input = map(float,[1,2,3])
print(list(list_of_input)[0])
print(list(list_of_input)[0])
IndexError: list index out of range
Why does this error occur?
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marco73824192
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Could not repro the error, its working on my end – shahidammer Sep 08 '18 at 07:22
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because when you generate use the function [map](https://docs.python.org/3/library/functions.html#map) this return a iterator, once this is converted to a list the [iterator](https://anandology.com/python-practice-book/iterators.html#the-iteration-protocol) pull all the values, , so the next time the list_of_input is converted to a list value will be a [] – Leonardo Orozco Sep 08 '18 at 07:32
2 Answers
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The conversion of a map to list is done only once, meaning map is a generator object and once you transform it to list, it gets exhausted : python 3: generator for map. So the error comes from second print statement and not the first.
thelogicalkoan
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in Python 3 map() returns an iterator not a list. When you pass this iterator to list the first time it consumes the iterator so the second time you get an empty list, hence the IndexError.
bruno desthuilliers
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