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PyPy — How can it possibly beat CPython?
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Q1. How is this possible?
Manual memory management (which is what CPython does with its counting) can be slower than automatic management in some cases.
Limitations in the implementation of the CPython interpreter preclude certain optimisations that PyPy can ...
Difference between Static and final?
I'm always confused between static and final keywords in java .
11 Answers
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capturing self strongly in this block is likely to lead to a retain cycle
... your implicit property access of self.timerDisp - you can't refer to self or properties on self from within a block that will be strongly retained by self.
You can get around this by creating a weak reference to self before accessing timerDisp inside your block:
__weak typeof(self) weakSelf = sel...
filter for complete cases in data.frame using dplyr (case-wise deletion)
Is it possible to filter a data.frame for complete cases using dplyr? complete.cases with a list of all variables works, of course. But that is a) verbose when there are a lot of variables and b) impossible when the variable names are not known (e.g. in a function that processes any data.frame).
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URL encoding the space character: + or %20?
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When data that has been entered into HTML forms is submitted, the form field names and values are encoded and sent to the server in an HTTP request message using method GET or POST, or, historically, via email. The encoding used by default is based on a very early ver...
Why Choose Struct Over Class?
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According to the very popular WWDC 2015 talk Protocol Oriented Programming in Swift (video, transcript), Swift provides a number of features that make structs better than classes in many circumstances.
Structs are preferable if...
How do I delete an item or object from an array using ng-click?
...son this is undefined. Plunker/jsfiddle perhaps?
– Tjorriemorrie
Sep 19 '13 at 10:59
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.indexOf(...
Heap vs Binary Search Tree (BST)
... Type BST (*) Heap
Insert average log(n) 1
Insert worst log(n) log(n) or n (***)
Find any worst log(n) n
Find max worst 1 (**) 1
Create worst n log(n) n
Delete worst log(n) log(n)
All average times on this table are the same as their...
CSS selector for “foo that contains bar”? [duplicate]
Is there a way to make a CSS Selector that matches the following?
3 Answers
3
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Changing default shell in Linux [closed]
...tailed command is chsh -s /bin/bash.
It will prompt you to enter your password.
Your default login shell is /bin/bash now. You must log out and log back in to see this change.
The following is quoted from man page:
The chsh command changes the user login shell. This determines the
name
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