List comprehension

Question

Is it possible to do try and except using list comprehension in python? For example : I have list [1,2,3,'h',4], I would like to calculate square of all integers and keep 'h' as it is. [1, 4, 9,'h', 16]

Answer 1

I don't think you can use try/except in a list comprehension, but you don't need to because you can get the desired result with if/else:

lst = [1, 2, 3, 'h', 4]

squares = [n**2 if isinstance(n, int) or isinstance(n, float) else n for n in lst]

print(squares) # [1, 4, 9, 'h', 16]

/Edit: This one makes it easier to add more numeric data types:

squares2 = [n**2 if any(isinstance(n, t) for t in (int, float)) else n for n in lst]

print(squares2)

/Edit²: using numbers.Number will detect most numerical types:

from numbers import Number

lst = [1, 2, 3, 4.5, 'h', 6, 7j]

squares3 = [n**2 if isinstance(n, Number) else n for n in lst]

print(squares3) # [1, 4, 9, 20.25, 'h', 36, (-49+0j)]

Answer 2

Gordon I'm sure 👌☺️

Answer 3

Wow, but can he understand your answer? 😅

Answer 4

Thanks Anna ..it was helpful:)

Answer 5

If it's only about int or not int, I would use this pattern:

[i**2 if type(i)==int else i for i in l]