if coin == 25 | 10 | 5:
If I replace the ‘|’ with ‘or’ the code runs just fine. I’m not sure why I can’t use ‘|’ in the same statement.
Doing the following doesn’t work either:
if coin == 25 | coin == 10 | coin == 5:
I know bitwise operators can only be used with integers, but other then that is there another difference from logical operators?
Thanks. I think I understand why I wouldn’t want to use it in this case. But what is an example of where I can use it? This makes me think I should avoid using bitwise operators with integers and keep it to strings only, but I know that’s not true from what I’ve learned.
Aside from operations on bitfields, a bitwise operator can be useful in several “non bits” cases. For instance:
value & 1evaluates to 1 ifvalueis odd (and will evaluate to True in anifstatement)value >> 1dividesvalueby 2 (integer division)But usually bitwise operators are for when you want to manipulate bits in values. For instance:
value | 5returnsvaluewith bits 1 and 3 set to Truevalue & 0xffffreturns the 16 least-significant bits invalue(usually you do this to make sure it will fit in 2 bytes in memory for example)value & (0xffff ^ 5)returns the lower 16 bits ofvaluewith bits 1 and 3 set to FalseEtc.
Thank you for the reply. It seems bitwise operators are somewhat of an advanced concept that I may revisit down the road.
honestly yes you’re probably not going to use them a lot, if at all, especially in python
You might use them with sets:
a = {1, 2, 3} b = {2, 3, 4} a | b # {1, 2, 3, 4} a & b # {2, 3} a ^ b # {1, 4} a - b # {1} b - a # {4}They use the same symbols, but they’re not bitwise operators anymore.
True, but it has the same semantics.
They’re quite simple. Just convert the values to binary and apply the applicable truth tables. Just remember operator precedence when you use them, and in doubt, don’t trust your luck and apply parentheses generously 🙂
And write generous unit tests so the next person doesn’t accidentally mess it up.
python in general tends toward readability over performance optimisation… you’re right they’re an advanced concept, and i’d say if you ever use bitwise operators in python they should be wrapped in some descriptive and very minimal function: treat it like a black box, because the next person that comes along likely won’t understand what’s happening without a pretty good description
a bit field is just not a descriptive data structure, so manipulate it directly as little as possible
i’d also say that most peoples use of bitwise operators is when unpacking external data formats (network traffic, operating system primitives, files formats, etc) and they’re usually wrapped in data structures that make those things more pythonic
unless you know you need bitwise operators, you probably don’t need bitwise operators
I use that in match case operations, but usually when is just two possibilities, try something like this and see if works
match coin:
case 5 | 10 | 20:
…
Edit: just tested and it’s works.