I had the following code:
return [p.to_dict() for p in points]
I changed it to only print every nth row:
n = 100
count = 0
output = []
for p in points:
if (count % n == 0):
output.append(p.to_dict())
count += 1
return output
Is there a more pythonic way to write this, to acheive the same result?
use enumerate and modulo on the index in a modified list comprehension to filter the ones dividable by n:
return [p.to_dict() for i,p in enumerate(points) if i % n == 0]
List comprehension filtering is good, but in that case, eduffy answer which suggests to use slicing with a step is better since the indices are directly computed. Use the filter part only when you cannot predict the indices.
Improving this answer even more: It's even better to use itertools.islice so not temporary list is generated:
import itertools
return [p.to_dict() for p in itertools.islice(points,None,None,n)]
itertools.islice(points,None,None,n) is equivalent to points[::n] but performing lazy evaluation.
The list slicing syntax takes an optional third argument to define the "step". This take every 3rd in a list:
>>> range(10)
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
>>> range(10)[::3]
[0, 3, 6, 9]
you can use enumerate with list comprehension.
[p.to_dict() for i, p in enumerate(points) if i %100 == 0]
points? Can you provide some data / reproducible code?