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Rails select helper - Default selected value, how?
...g to edit your record.
You need to set the default to your existing value and then only set it to the actual default if you don't have a value. Like so:
f.select :field, options_for_select(value_array, f.object.field || default_value)
For anyone not familiar with f.object.field you always use f....
“Add as Link” for folders in Visual Studio projects
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+1. You could also use <Content ...>, and add <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory> to make Visual Studio copy the resources on build.
– Markus Jarderot
May 18 '12 at 18:12
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How to suppress Pandas Future warning ?
When I run the program, Pandas gives 'Future warning' like below every time.
3 Answers
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Equivalent of varchar(max) in MySQL?
...eat to these column types was that they usually required special functions and statements to access and modify the data (e.g. READTEXT, WRITETEXT, and UPDATETEXT)
In SQL Server 2005, varchar(max) was introduced to unify the data and queries used to retrieve and modify data in large columns. The dat...
How to make a div with no content have a width?
...eight because it doesn't force a height. Say your font-size is set to 16px and your padding is 15px. Your div will retain the same height before and after text is added to the div (assuming it's all on one line)
– eroedig
Jul 16 '15 at 18:56
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How to check 'undefined' value in jQuery
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JQuery library was developed specifically to simplify and to unify certain JavaScript functionality.
However if you need to check a variable against undefined value, there is no need to invent any special method, since JavaScript has a typeof operator, which is simple, fast and...
Selectors in Objective-C?
First, I'm not sure I really understand what a selector is. From my understanding, it's the name of a method, and you can assign it to a class of type 'SEL' and then run methods such as respondToSelector to see if the receiver implements that method. Can someone offer up a better explanation?
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How to plot two histograms together in R?
I am using R and I have two data frames: carrots and cucumbers. Each data frame has a single numeric column which lists the length of all measured carrots (total: 100k carrots) and cucumbers (total: 50k cucumbers).
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Git update submodules recursively
...d submodules may not be updated. In that case, you should also run the command without --init option.
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Can I set max_retries for requests.request?
The Python requests module is simple and elegant but one thing bugs me.
It is possible to get a requests.exception.ConnectionError with a message like:
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