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Convert data.frame columns from factors to characters
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Just following on Matt and Dirk. If you want to recreate your existing data frame without changing the global option, you can recreate it with an apply statement:
bob <- data.frame(lapply(bob, as.character), stringsAsFactors=FALSE)
This will...
At runtime, find all classes in a Java application that extend a base class
...ns. I mistakenly figured this would be as easy as it is in the .Net world and this answer has saved me a lot of time.
– akmad
Oct 1 '12 at 19:55
1
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Input with display:block is not a block, why not?
...hy does display:block;width:auto; on my text input not behave like a div and fill the container width?
7 Answers
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How much faster is C++ than C#?
...++ code. However C++ code used to be significantly faster for a long time, and also today still is in many cases. This is mainly due to the more advanced JIT optimizations being complicated to implement, and the really cool ones are only arriving just now.
So C++ is faster, in many cases. But this ...
How to detect unused methods and #import in Objective-C
...ne app, I realized that my code is quite dirty, containing several #import and methods that are not called or useful at all.
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cleanest way to skip a foreach if array is empty [duplicate]
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There are a million ways to do this.
The first one would be to go ahead and run the array through foreach anyway, assuming you do have an array.
In other cases this is what you might need:
foreach ((array) $items as $item) {
print $item;
}
Note: to all the people complaining about typecas...
Python argparse ignore unrecognised arguments
Optparse, the old version just ignores all unrecognised arguments and carries on. In most situations, this isn't ideal and was changed in argparse. But there are a few situations where you want to ignore any unrecognised arguments and parse the ones you've specified.
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How to get a file or blob from an object URL?
I am allowing the user to load images into a page via drag&drop and other methods. When an image is dropped, I'm using URL.createObjectURL to convert to an object URL to display the image. I am not revoking the url, as I do reuse it.
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Detecting an “invalid date” Date instance in JavaScript
I'd like to tell the difference between valid and invalid date objects in JS, but couldn't figure out how:
46 Answers
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Bypass popup blocker on window.open when JQuery event.preventDefault() is set
... url: url,
dataType: 'json',
data: data,
success: callback
});
...and so you can make your $.getJSON call synchronous by mapping your params to the above and adding async: false:
$.ajax({
url: "redirect/" + pageId,
async: false,
dataType: "json",
data: {},
s...