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How to select option in drop down using Capybara
...t method, you can see that what it does when you pass a from key is essentially:
find(:select, from, options).find(:option, value, options).select_option
In other words, it finds the <select> you're interested in, then finds the <option> within that, then calls select_option on the &l...
Xcode 4 - “Valid signing identity not found” error on provisioning profiles on a new Macintosh insta
... iPhone apps with using XCode 4.
I now have a new Macintosh with a new install of... everything.
16 Answers
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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)
You can also do things like this, to use all variables but...
Calculating moving average
...y helpful though. There doesn't seem to be a built-in function in R will allow me to calculate moving averages. Do any packages provide one? Or do I need to write my own?
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How to permanently disable region-folding in Visual Studio 2008
... folding in visual studio 2008? Some of my colleagues love it, but I personally always want to see all the code, and never want code folded out of sight. I'd like a setting that means my copy of Visual Studio never folds #regions or function bodies.
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How to initialize array to 0 in C?
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Global variables and static variables are automatically initialized to zero. If you have simply
char ZEROARRAY[1024];
at global scope it will be all zeros at runtime. But actually there is a shorthand syntax if you had a local array. If an array is partially initialized, e...
Formula to determine brightness of RGB color
...Note that both of these emphasize the physiological aspects: the human eyeball is most sensitive to green light, less to red and least to blue.
– Bob Cross
Feb 27 '09 at 19:28
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How to set timeout on python's socket recv method?
...lect() to wait until data is available or until the timeout occurs. Only call recv() when data is actually available. To be safe, we also set the socket to non-blocking mode to guarantee that recv() will never block indefinitely. select() can also be used to wait on more than one socket at a time...
Maintain git repo inside another git repo
... Git submodules.
Git addresses this issue using submodules. Submodules allow you to keep a Git repository as a subdirectory of another Git repository. This lets you clone another repository into your project and keep your commits separate.
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Does every Javascript function have to return a value?
...ow level, the return is translated into some sort of jump. If a function really returned nothing at all, there would be no way of knowing what and when to call the next function, or to call event handlers and the like.
So to recap: No, a JS function needn't return anything as far as your code goes....