Design a logical expression equivalent to the following statement:
x
is a list of three or five elements, the second element of which is
To answer the specific question:
isinstance(x[0], (int, float))
This checks if x[0]
is an instance of any of the types in the tuple (int, float)
.
You can add bool
in there, too, but it's not necessary, because bool
is itself a subclass of int
.
Doc reference:
To comment on your current code, you shouldn't rely on interning of short strings. You are supposed to compare strings with the ==
operator:
x[1] == 'Hip'
Python 2
import types
x = False
print(type(x) == types.BooleanType) # True
Python 3
# No need to import types module
x = False
print(type(x) == bool) # True
I like to keep it simple to read.. This will accept bool, string, number and read it to a bool
def var2bool(v):
if type(v) == type(True):
res = v
elif type(v) == type(0):
if v == 0:
res = False
else:
res = True
elif v.lower() in ("yes", "true", "t", "1"):
res = True
else:
res = False
return res
I follow the recent answer who tell to use type
and it seems to be the incorrect way according to pylint
validation:
I got the message:
C0123: Using type() instead of isinstance() for a typecheck. (unidiomatic-typecheck)
Even if it's an old answer, the correct one is the accepted answer of @Lev Levitsky:
isinstance(x[0], (int, float))
Easiest i would say:
type(x) == type(True)
In python3 this would be: type(x)==bool
see example.