Menu
To check if a variable is equal to all of multiple values, use the logical AND (&&) operator to chain multiple equality comparisons. If all comparisons return true , all values are equal to the variable. Copied! We used the logical AND (&&) operator to chain multiple equality checks.
To test multiple variables x , y , z against a value in Python, use the expression value in {x, y, z} . Checking membership in a set has constant runtime complexity. Thus, this is the most efficient way to test multiple variables against a value.
if x == 1 or y == 1 or z == 1: x and y are otherwise evaluated on their own ( False if 0 , True otherwise). You can shorten that using a containment test against a tuple: if 1 in (x, y, z):
The is keyword is used to test if two variables refer to the same object. The test returns True if the two objects are the same object. The test returns False if they are not the same object, even if the two objects are 100% equal. Use the == operator to test if two variables are equal.
("Jesse" or "jesse")
The above expression tests whether or not "Jesse" evaluates to True. If it does, then the expression will return it; otherwise, it will return "jesse". The expression is equivalent to writing:
"Jesse" if "Jesse" else "jesse"
Because "Jesse" is a non-empty string though, it will always evaluate to True and thus be returned:
>>> bool("Jesse") # Non-empty strings evaluate to True in Python
True
>>> bool("") # Empty strings evaluate to False
False
>>>
>>> ("Jesse" or "jesse")
'Jesse'
>>> ("" or "jesse")
'jesse'
>>>
This means that the expression:
name == ("Jesse" or "jesse")
is basically equivalent to writing this:
name == "Jesse"
In order to fix your problem, you can use the in operator:
# Test whether the value of name can be found in the tuple ("Jesse", "jesse")
if name in ("Jesse", "jesse"):
Or, you can lowercase the value of name with str.lower and then compare it to "jesse" directly:
# This will also handle inputs such as "JeSSe", "jESSE", "JESSE", etc.
if name.lower() == "jesse":
if name in ("Jesse", "jesse"):
would be the correct way to do it.
Although, if you want to use or, the statement would be
if name == 'Jesse' or name == 'jesse':
>>> ("Jesse" or "jesse")
'Jesse'
evaluates to 'Jesse', so you're essentially not testing for 'jesse' when you do if name == ("Jesse" or "jesse"), since it only tests for equality to 'Jesse' and does not test for 'jesse', as you observed.
If you want case-insensitive comparison, use lower or upper:
if name.lower() == "jesse":
The or operator returns the first operand if it is true, otherwise the second operand. So in your case your test is equivalent to if name == "Jesse".
The correct application of or would be:
if (name == "Jesse") or (name == "jesse"):
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With