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LaTeX table positioning
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edited Dec 14 '14 at 14:18
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How to succinctly write a formula with many variables from a data frame?
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There is a special identifier that one can use in a formula to mean all the variables, it is the . identifier.
y <- c(1,4,6)
d <- data.frame(y = y, x1 = c(4,-1,3), x2 = c(3,9,8), x3 = c(4,-4,-2))
mod <- lm(y ~ ., data = d...
Creating a blurring overlay view
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You can use UIVisualEffectView to achieve this effect. This is a native API that has been fine-tuned for performance and great battery life, plus it's easy to implement.
Swift:
//only apply the blur if the user hasn't disabled transparenc...
How do I calculate square root in Python?
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sqrt=x**(1/2) is doing integer division. 1/2 == 0.
So you're computing x(1/2) in the first instance, x(0) in the second.
So it's not wrong, it's the right answer to a different question.
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SQL Server - where is “sys.functions”?
...andy and I use them all the time.
I'm not sure what Microsoft's rationale is for not including a sys.functions equivalent in SQL Server 2005 (or SQL Server 2008, as far as I can tell), but it's easy enough to roll your own:
CREATE VIEW my_sys_functions_equivalent
AS
SELECT *
FROM sys.objects
WHERE...
Can I run javascript before the whole page is loaded?
I want to run a bit of javascript before the whole page has loaded. Is this possible? Or does the code start to execute on </html> ?
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How can I get the MAC and the IP address of a connected client in PHP?
... to know the MAC and the IP address of the connect clients, how can I do this in PHP?
16 Answers
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How to get the client IP address in PHP [duplicate]
...['REMOTE_ADDR'] contains the real IP address of the connecting party. That is the most reliable value you can find.
However, they can be behind a proxy server in which case the proxy may have set the $_SERVER['HTTP_X_FORWARDED_FOR'], but this value is easily spoofed. For example, it can be set by ...
ASP.NET Web API OperationCanceledException when browser cancels the request
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This is a bug in ASP.NET Web API 2 and unfortunately, I don't think there's a workaround that will always succeed. We filed a bug to fix it on our side.
Ultimately, the problem is that we return a cancelled task to ASP.NET in ...
What's the point of g++ -Wreorder?
The g++ -Wall option includes -Wreorder. What this option does is described below. It is not obvious to me why somebody would care (especially enough to turn this on by default in -Wall).
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