Found 10476 Articles for Python

What is operator binding in Python?

Ankitha Reddy
Updated on 30-Jul-2019 22:30:22

491 Views

For expressions like − a == b first the python interpreter looks up the __eq__() method on the object a. If it finds that, then executes that with b as argument, ie, a.__eq__(b). If this method returns a NotImplemented, then it tries doind just the reverse, ie, it tries to call, b.__eq__(a)

How can we speed up Python "in" operator?

karthikeya Boyini
Updated on 30-Jul-2019 22:30:22

590 Views

The python operator performs very badly in a list, O(n), because it traverses the whole list. You can use something like a set or a dict(hashed data structures that have very fast lookups) to get the same result in ~O(1) time!But this also depends on the type of data structure you're looking at. This is because while lookups in sets/dicts are fast, insertion may take more time than list. So this speedup really depends on the type.

How can we use Python Ternary Operator Without else?

Abhinaya
Updated on 05-Mar-2020 07:37:19

1K+ Views

If you want to convert a statement like −if :    to a single line, You can use the single line if syntax to do so −if : Another way to do this is leveraging the short-circuiting and operator like − and If is false, then short-circuiting will kick in and the right-hand side won't be evaluated. If is true, then the right-hand side will be evaluated and will be evaluated.

What is Practical Use of Reversed Set Operators in Python?

Govinda Sai
Updated on 30-Jul-2019 22:30:22

161 Views

Reversed set operators are operators that are defined as:s & z corresponds to s.__and__(z) z & s corresponds to s.__rand__(z)These don't make much sense in normal operations like and, add, or, etc of simple objects. However in case of inheritence, reversed operations are particularly useful when dealing with subclasses because if the right operand is a subclass of the left operand the reversed operation is attempted first. You may have different implementations in parent and child classes.These reversed operations are also used if the first operand returns NotImplemented.

How to do bitwise complement on a 16-bit signal using Python?

Ramu Prasad
Updated on 05-Mar-2020 07:33:37

320 Views

If you want to get an inversion of only first 16 bits of a number, you can take a xor of that number with 65535(16 1s in binary). examplea = 3 # 11 in binary b = a ^ 65535 print(bin(b))OutputThis will give the output −0b1111111111111100

How to do twos complement on a 16-bit signal using Python?

karthikeya Boyini
Updated on 17-Jun-2020 11:53:54

1K+ Views

If you want to get an inversion of only first 16 bits of a number, you can take a xor of that number with 65535(16 1s in binary). Forgetting a 2s complement, just add one to the result. For example,Examplea = 3 # 11 in binary b = (a ^ 65535) + 1 print(bin(b))OutputThis will give the output:0b1111111111111101

Can we change operator precedence in Python?

Samual Sam
Updated on 30-Jul-2019 22:30:22

487 Views

No this cannot be done. It's part of the Python language itself. That's how the language parses the expressions and builds parse and syntax trees. From the documentation:When performing mathematical operations with mixed operators, it is important to note that Python determines which operations to perform first, based on a pre-determined precedence. This precedence follows a similar precedence to most programming languages.

How to change the look of Python operators?

Sai Subramanyam
Updated on 30-Jul-2019 22:30:22

171 Views

Python and most mainstream languages do not allow changing how operators look. If you're trying to replace something like a == b with a equals b, you can't do that. In Python the restriction is quite intentional — an expression such as a equals b would look ungrammatical to any reader familiar with Python.

How to access nested Python dictionary items via a list of keys?

Prabhas
Updated on 05-Mar-2020 07:19:36

2K+ Views

The easiest and most readable way to access nested properties in a Python dict is to use for loop and loop over each item while getting the next value, until the end. exampledef getFromDict(dataDict, mapList): for k in mapList: dataDict = dataDict[k] return dataDict a = {    'foo': 45,'bar': {       'baz': 100,'tru': "Hello"    } } print(getFromDict(a, ["bar", "baz"]))OutputThis will give the output −100

How to put multi-line comments inside a Python dict()?

Samual Sam
Updated on 05-Mar-2020 09:58:45

374 Views

You can put comments like you normally would anywhere in a python script. But note that you can only put single line comments using #. Multiline comments act like strings and you cannot put just a string in between definition of a dict. For example, the following declaration is perfectly valid −ExampletestItems = {    'TestOne': 'Hello',    # 'TestTwo': None, }But the following is not −testItems = {    'TestOne': 'Hello',    """    Some random    multiline comment    """ }

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