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Random row selection in Pandas dataframe
... Thanks @eumiro. I also worked out that df.ix[np.random.random_integers(0, len(df), 10)] would also work.
– John
Apr 10 '13 at 10:58
7
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How to cast List to List
... No, it isn't. You would circumvent type safety if the above was allowed. Note that casting does not mean create a new list and copy over the items. It means handle the single instance as a different type, and thus you would have a list that contains potentially non-Customer objects with a...
Using R to download zipped data file, extract, and import data
...
Zip archives are actually more a 'filesystem' with content metadata etc. See help(unzip) for details. So to do what you sketch out above you need to
Create a temp. file name (eg tempfile())
Use download.file() to fetch the file into the temp....
node and Error: EMFILE, too many open files
...t indicates which resource is open. You'll probably see a number of lines all with the same resource name. Hopefully, that now tells you where to look in your code for the leak.
If you don't know multiple node processes, first lookup which process has pid 12211. That'll tell you the process.
In ...
Why was the switch statement designed to need a break?
...
Many answers seem to focus on the ability to fall through as the reason for requiring the break statement.
I believe it was simply a mistake, due largely because when C was designed there was not nearly as much experience with how these constructs would be used.
Peter ...
Android studio - Failed to find target android-18
...
I think you might not have the Android-18 sdk installed. Go to Tools > Android > SDK Manager and check to see if Android 4.3 (API 18) is installed.
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How do I replace NA values with zeros in an R dataframe?
...then assign it to the location/name on the left. In this case, we aren't really "doing" anything - just making zeroes. The left side is saying: look at the d object, inside the d object (the square brackets), find all the elements that return TRUE (is.na(d) returns a logical for each element). Once...
Array.push() if does not exist?
... it doesn't then just push the item into the array:
var newItem = "NEW_ITEM_TO_ARRAY";
var array = ["OLD_ITEM_1", "OLD_ITEM_2"];
array.indexOf(newItem) === -1 ? array.push(newItem) : console.log("This item already exists");
console.log(array)
...
How to do URL decoding in Java?
... {
String result = java.net.URLDecoder.decode(url, StandardCharsets.UTF_8.name());
} catch (UnsupportedEncodingException e) {
// not going to happen - value came from JDK's own StandardCharsets
}
Java 10 added direct support for Charset to the API, meaning there's no need to catch Unsuppor...
How do you reference a capture group with regex find and replace in Visual Studio 2012, 2013, 2015,
...gular expressions' is checked, and put the following as the text to find:
_platformActions.InstallApp\((.+)\)
And the following as the text to replace it with:
this.Platform().App($1).Install()
Note: As SLaks points out in a comment below, the change in regex syntax is due to VS2012 switching to...