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The 'json' native gem requires installed build tools
...on my windows 7 machine. Now I tried to install the JSON gem using the command, "gem install json" and got the following error.
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How to keep index when using pandas merge
I would like to merge two DataFrames , and keep the index from the first frame as the index on the merged dataset. However, when I do the merge, the resulting DataFrame has integer index. How can I specify that I want to keep the index from the left data frame?
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How to generate a number of most distinctive colors in R?
I am plotting a categorical dataset and want to use distinctive colors to represent different categories. Given a number n , how can I get n number of MOST distinctive colors in R? Thanks.
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The name 'ConfigurationManager' does not exist in the current context
...The code is ASP.NET + C#. I have added System.Configuration to reference and also mentioned with using. But still it wouldn't accept the assembly.
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Getting the array length of a 2D array in Java
I need to get the length of a 2D array for both the row and column. I’ve successfully done this, using the following code:
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Check for changes to an SQL Server table?
...of the database in any way? My preferred programming environment is .NET and C#.
8 Answers
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How can I tell Rails to use RSpec instead of test-unit when creating a new Rails app?
I have test-unit installed and rspec installed (along with -core , -expectations , -mocks and -rails version 2.6.x). When I run the command rails new foo , it uses test-unit to generate the test stub files instead of rspec .
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C++ error: undefined reference to 'clock_gettime' and 'clock_settime'
...ut I can't seem to get this to work. It works fine on my school computers and I don't know what I am not doing. I have checked usr/include and time.h is there just fine. Here is the code:
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Move capture in lambda
...ref( T && x )
{
return rref_impl<T>{ std::move(x) };
}
And here's a test case for that function that ran successfully on my gcc 4.7.3.
int main()
{
std::unique_ptr<int> p{new int(0)};
auto rref = make_rref( std::move(p) );
auto lambda =
[rref]() mutabl...
How do I center floated elements?
I'm implementing pagination, and it needs to be centered. The problem is that the links need to be displayed as block, so they need to be floated. But then, text-align: center; doesn't work on them. I could achieve it by giving the wrapper div padding of left, but every page will have a different ...