CODEWITHSUNDEEP
pythonlisttypescastingdataset
Mark Corrigan
Mark Corrigan

Reputation: 554

List type conversion python

I have a dataset which the pdb debugger tells me looks like this;

set1 : [(4.4, ), (4.8, ), (4.2, ), (4.0, ), (4.2, ), (4.8, ), (2.0, ), (2.4, ), (3.0, )]

I need it to be in the format below;

set2 : [4.4, 4.8, 4.2, 4.0, 4.2, 4.8, 2.0, 2.4, 3.0]

What types, or variations of types, are set 1 and 2 and how do you cast, or otherwise, set 1 into set 2.

I'm new to python and required to do this in a rush so there's no time for me to learn in the detail I should just now - any help will be greatly appreciated.

Thanks!

Upvotes: 1

Views: 85

Answers (3)

Abhijit
Abhijit

Reputation: 63777

The data looks very familiar and deserves a treatment with zip

print list(zip(*set1)[0])

Upvotes: 0

Pablo Francisco Pérez Hidalgo
Pablo Francisco Pérez Hidalgo

Reputation: 27702

Try with:

set1 = [(4.4, ), (4.8, ), (4.2, ), (4.0, ), (4.2, ), (4.8, ), (2.0, ), (2.4, ), (3.0, )]
set2 = map(lambda x: x[0], set1)

set1 is a list of one-element tuples, map returns the result of applying the function passed as first parameter to the collection passed as second parameter. In this answer, that function is the one that returns the first element of a tuple.

A more pythonic way to do this is to use list comprehension:

set2 = [x[0] for x in set1]

Upvotes: 1

sundar nataraj
sundar nataraj

Reputation: 8702

Try using itertools.chain 

from itertools import chain

set1 =[(4.4, ), (4.8, ), (4.2, ), (4.0, ), (4.2, ), (4.8, ), (2.0, ), (2.4, ), (3.0, )]

print list(chain.from_iterable(set1))
#output [4.4, 4.8, 4.2, 4.0, 4.2, 4.8, 2.0, 2.4, 3.0]

Upvotes: 0

Related Questions