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Replace a value in a data frame based on a conditional (`if`) statement
...character(junk$nm)
junk$nm[junk$nm == "B"] <- "b"
EDIT: And if indeed you need to maintain nm as factors, add this in the end:
junk$nm <- as.factor(junk$nm)
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How can I click a button behind a transparent UIView?
Let's say we have a view controller with one sub view. the subview takes up the center of the screen with 100 px margins on all sides. We then add a bunch of little stuff to click on inside that subview. We are only using the subview to take advantage of the new frame ( x=0, y=0 inside the subview i...
Attempt to present UIViewController on UIViewController whose view is not in the window hierarchy
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Where are you calling this method from? I had an issue where I was attempting to present a modal view controller within the viewDidLoad method. The solution for me was to move this call to the viewDidAppear: method.
My presumption is ...
What does “while True” mean in Python?
... forever. The while statement takes an expression and executes the loop body while the expression evaluates to (boolean) "true". True always evaluates to boolean "true" and thus executes the loop body indefinitely. It's an idiom that you'll just get used to eventually! Most languages you're likely t...
What is the printf format specifier for bool?
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There is no format specifier for bool types. However, since any integral type shorter than int is promoted to int when passed down to printf()'s variadic arguments, you can use %d:
bool x = true;
printf("%d\n", x); // prints 1
But why not:
printf(x ? "true" : ...
Positions fixed doesn't work when using -webkit-transform
...effects together at the same time.
I would suggest adding some Webkit only CSS into your stylesheet and making the transformed div an image and using it as the background.
@media screen and (-webkit-min-device-pixel-ratio:0) {
/* Webkit-specific CSS here (Chrome and Safari) */
#transformed_d...
Comparison of CI Servers? [closed]
...uous integration (CI) Servers (esp. focusing
on .NET) and couldn't find any.
13 Answers
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What does this symbol mean in JavaScript?
This is a collection of questions that come up every now and then about syntax in JavaScript. This is also a Community Wiki, so everyone is invited to participate in maintaining this list.
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Android: Temporarily disable orientation changes in an Activity
My main activity has some code that makes some database changes that should not be interrupted. I'm doing the heavy lifting in another thread, and using a progress dialog which I set as non-cancellable. However, I noticed that if I rotate my phone it restarts the activity which is REALLY bad for the...
Why does Vim save files with a ~ extension?
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The *.ext~ file is a backup file, containing the file as it was before you edited it.
The *.ext.swp file is the swap file, which serves as a lock file and contains the undo/redo history as well as any other internal info Vim needs. In case of a crash you can re-open your file and Vim will resto...