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Android, getting resource ID from string?
...ne of my classes. It needs to use both the id that the reference points to and also it needs the string. How should I best achieve this?
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Static Initialization Blocks
...the constructor's job to initialize fields.
– Martin Andersson
Apr 1 '13 at 18:56
2
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Condition within JOIN or WHERE
...u only those records that have an order dated later than May 15, 2009 thus converting the left join to an inner join.
The second will give those records plus any customers with no orders. The results set is very different depending on where you put the condition. (Select * is for example purposes on...
Why does an overridden function in the derived class hide other overloads of the base class?
...ding happens, people who respond either say that this called "name hiding" and explain how it works (which you probably already know), or explain how to override it (which you never asked about), but nobody seems to care to address the actual "why" question.
The decision, the rationale behind the n...
Log to the base 2 in python
....log(x, 2.0)
log2 = math.log2(x) # python 3.4 or later
Thanks @akashchandrakar and @unutbu.
float → int math.frexp(x)
If all you need is the integer part of log base 2 of a floating point number, extracting the exponent is pretty efficient:
log2int_slow = int(math.floor(math.log(x, 2.0)...
What does the “map” method do in Ruby?
...example:
names = ['danil', 'edmund']
# here we map one array to another, convert each element by some rule
names.map! {|name| name.capitalize } # now names contains ['Danil', 'Edmund']
names.each { |name| puts name + ' is a programmer' } # here we just do something with each element
The output:...
开源MQTT网关：EMQX vs Mosquitto - 创客硬件开发 - 清泛IT社区，为创新赋能！
引言物联网开发者需要为自己的物联网项目选择合适的 MQTT 消息产品或服务，从而构建可靠高效的基础数据层，保障上层物联网业务。目前市面上有很多开源的 MQTT 产品，在性能功能等方面各有优点。本文将选取目前最为流行的...
How to get duration, as int milli's and float seconds from ?
I'm trying to use chrono library for timers and durations.
4 Answers
4
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What is __stdcall?
I'm learning about Win32 programming, and the WinMain prototype looks like:
8 Answers
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How to copy text programmatically in my Android app?
I'm building an Android app and I want to copy the text value of an EditText widget. It's possible for the user to press Menu+A then Menu+C to copy the value, but how would I do this programmatically?
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