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In Python, when should I use a function instead of a method?
...sulation which is so dear to OO design.
The encapsulation principal is really what this comes down to: as a designer you should hide everything about the implementation and class internals which it is not absolutely necessarily for any user or other developer to access. Because we deal with instan...
How to find if a native DLL file is compiled as x64 or x86?
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You can use DUMPBIN too. Use the /headers or /all flag and its the first file header listed.
dumpbin /headers cv210.dll
64-bit
Microsoft (R) COFF/PE Dumper Version 10.00.30319.01
Copyright (C) Microsoft Corporation. All rights reserved.
Dump of file cv210.dll
PE ...
How much is the overhead of smart pointers compared to normal pointers in C++?
..._ptr always has memory overhead for reference counter, though it is very small.
std::unique_ptr has time overhead only during constructor (if it has to copy the provided deleter and/or null-initialize the pointer) and during destructor (to destroy the owned object).
std::shared_ptr has time overhe...
How to get my IP address programmatically on iOS/macOS?
I would like to obtain my iPad's IP address programmatically.
How can I query the networking subsystem to find out what my IPv4 (and IPv6) addresses are?
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ios app maximum memory budget
...ered your own question: try not to go beyond the 70 Mb limit, however it really depends on many things: what iOS version you're using (not SDK), how many applications running in background, what exact memory you're using etc.
Just avoid the instant memory splashes (e.g. you're using 40 Mb of RAM, a...
Only read selected columns
...g","Sep","Oct","Nov","Dec"))
dat <- fread("data.txt", drop = c(8:13))
All result in:
> data
Year Jan Feb Mar Apr May Jun
1 2009 -41 -27 -25 -31 -31 -39
2 2010 -41 -27 -25 -31 -31 -39
3 2011 -21 -27 -2 -6 -10 -32
UPDATE: When you don't want fread to return a data.table, use the data.ta...
Select count(*) from multiple tables
How can I select count(*) from two different tables (call them tab1 and tab2 ) having as result:
18 Answers
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Retain cycle on `self` with blocks
...nswered Dec 4 '10 at 8:14
Lily BallardLily Ballard
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How to convert currentTimeMillis to a date in Java?
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Calendar objects are generally considered quite large, so should be avoided when possible. A Date object is going to be better assuming it has the functionality you need. "Date date=new Date(millis);" provided in the other answer by user AVD is going ...
Check a radio button with javascript
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Technically it's CSS selector syntax. jQuery just borrowed and extended it
– Tim Seguine
Jan 16 '14 at 16:10
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