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find() with nil when there are no records
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Yes, just do:
Challenge.find_by_id(10)
For Rails 4 and 5:
Challenge.find_by(id: 10)
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What are all the common undefined behaviours that a C++ programmer should know about? [closed]
...amount greater than or equal to the number of bits in the number (e.g. int64_t i = 1; i <<= 72 is undefined)
Types, Cast and Const
Casting a numeric value into a value that can't be represented by the target type (either directly or via static_cast)
Using an automatic variable before it has ...
How to configure socket connect timeout
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147
I found this. Simpler than the accepted answer, and works with .NET v2
Socket socket = new Soc...
Ruby on Rails: Where to define global constants?
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Holger JustHolger Just
43.4k1414 gold badges9393 silver badges108108 bronze badges
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Xcode 4 - build output directory
I have problems with setting up/locating my output files in Xcode4 (beta 5). They are placed somewhere in ~/Library/Developer/ugly_path/... . I can't even select "show in finder" on my products. It is the same for a simple C project, Foundation tool and even Cocoa bundle. A Debugging works fine.
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“Remote System Explorer Operation” causing freeze for couple of seconds
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answered Mar 28 '16 at 9:14
Q9703Q9703
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How to do exponential and logarithmic curve fitting in Python? I found only polynomial fitting
... 19, 30, 35, 51])
>>> numpy.polyfit(numpy.log(x), y, 1)
array([ 8.46295607, 6.61867463])
# y ≈ 8.46 log(x) + 6.62
For fitting y = AeBx, take the logarithm of both side gives log y = log A + Bx. So fit (log y) against x.
Note that fitting (log y) as if it is linear will emphasize sm...
sizeof single struct member in C
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204
Although defining the buffer size with a #define is one idiomatic way to do it, another would be...
How do I “commit” changes in a git submodule? [duplicate]
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430
A submodule is its own repo/work-area, with its own .git directory.
So, first commit/push you...
Convert a PHP object to an associative array
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1442
Just typecast it
$array = (array) $yourObject;
From Arrays:
If an object is converted t...