Python Boolean: Difference between revisions
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Tag: Manual revert |
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</syntaxhighlight> | </syntaxhighlight> | ||
=What is True?= | =What is True?= | ||
The following values evaluate to <code>False</code> in Python. Everything else evaluates to <code>True</code>. | |||
* boolean <code>False</code> | |||
* <code>None</code> | |||
* zero integer <code>0</code> | |||
* zero float <code>0.0</code> | |||
* empty string <code>''</code> | |||
* empty list <code>[]</code> | |||
* empty tuple <code>()</code> | |||
* empty dict <code>{}</code> | |||
* empty set <code>set()</code> | |||
=Operators= | =Operators= | ||
| Line 14: | Line 24: | ||
<syntaxhighlight lang='py'> | <syntaxhighlight lang='py'> | ||
assert (True | True) | assert (True | True) | ||
assert (True or True) | |||
assert (True | False) | assert (True | False) | ||
assert (True or False) | |||
assert (False | True) | assert (False | True) | ||
assert (False or True) | |||
assert not (False | False) | assert not (False | False) | ||
assert not (False or False) | |||
</syntaxhighlight> | </syntaxhighlight> | ||
| Line 34: | Line 48: | ||
Note that <code>+</code> applied to booleans contest to integers. | Note that <code>+</code> applied to booleans contest to integers. | ||
==AND: <tt>&</tt> and <tt>&=</tt>== | |||
<syntaxhighlight lang='py'> | |||
assert (True & True) | |||
assert (True and True) | |||
assert not (True & False) | |||
assert not (True and False) | |||
assert not (False & True) | |||
assert not (False and True) | |||
assert not (False & False) | |||
assert not (False and False) | |||
</syntaxhighlight> | |||
Latest revision as of 19:56, 16 May 2024
Internal
Overview
A boolean can be True or False.
x = True
type(x)
<class 'bool'>
What is True?
The following values evaluate to False in Python. Everything else evaluates to True.
- boolean
False None- zero integer
0 - zero float
0.0 - empty string
- empty list
[] - empty tuple
() - empty dict
{} - empty set
set()
Operators
OR: | and |=
assert (True | True)
assert (True or True)
assert (True | False)
assert (True or False)
assert (False | True)
assert (False or True)
assert not (False | False)
assert not (False or False)
l = [True, False]
b = False
for e in l:
b |= e
assert b
l = [False, False]
b = False
for e in l:
b |= e
assert not b
Note that + applied to booleans contest to integers.
AND: & and &=
assert (True & True)
assert (True and True)
assert not (True & False)
assert not (True and False)
assert not (False & True)
assert not (False and True)
assert not (False & False)
assert not (False and False)