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When to use a “has_many :through” relation in Rails?
I am trying to understand what has_many :through is and when to use it (and how). However, I am not getting it. I am reading Beginning Rails 3 and I tried Googling, but I am not able to understand.
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Force R not to use exponential notation (e.g. e+10)?
...a grey area. You need to recall that R will always invoke a print method, and these print methods listen to some options. Including 'scipen' -- a penalty for scientific display. From help(options):
‘scipen’: integer. A penalty to be applied when deciding to print
numeric value...
Read and parse a Json File in C#
I have spent the best part of two days "faffing" about with code samples and etc., trying to read a very large JSON file into an array in c# so I can later split it up into a 2d array for processing.
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Change IPython/Jupyter notebook working directory
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That worked for me on windows 10 pro. Just open CMD and type: jupyter notebook --notebook-dir="D:\change_this_path"
– TharsDimitris
Dec 14 '18 at 9:11
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Can I find out the return value before returning while debugging in Visual Studio?
...e easiest way to access it is by putting a breakpoint on the function call and step over (F10) the call.
Update for VS2015: boo! unfortunately, it doesn't appear to be in VS2015 (devenv v14)
Update for VS2017: it's back. (devenv v15)
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Cancel a UIView animation?
... is to create a new animation to your end point. Set a very short duration and make sure you use the +setAnimationBeginsFromCurrentState: method to start from the current state. When you set it to YES, the current animation is cut short. Looks something like this:
[UIView beginAnimations:nil contex...
How to bind RadioButtons to an enum?
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return Enum.Parse(targetType, parameterString);
}
#endregion
}
And in the XAML-Part you use:
<Grid>
<Grid.Resources>
<l:EnumBooleanConverter x:Key="enumBooleanConverter" />
</Grid.Resources>
<StackPanel >
<RadioButton IsChecked="{...
Is DateTime.Now the best way to measure a function's performance?
I need to find a bottleneck and need to accurately as possible measure time.
15 Answers
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Get the device width in javascript
... than the device screen size.
Typically, when dealing with mobile devices AND desktop browsers I use the following:
var width = (window.innerWidth > 0) ? window.innerWidth : screen.width;
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Reverse Range in Swift
...here for the bounds.
Earlier edit for Swift 1.2: As of Xcode 6 Beta 4, by and ReverseRange don't exist anymore :[
If you are just looking to reverse a range, the reverse function is all you need:
for i in reverse(1...5) { println(i) } // prints 5,4,3,2,1
As posted by 0x7fffffff there is a new s...