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Determine the data types of a data frame's columns
...ation as a vector (i.e. you don't need it to do something else programmatically later), just use str(foo).
In both cases foo would be replaced with the name of your data frame.
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Xcode 5: Code signing entitlement errors
...both rows, however, I saw the "Any iOS SDK" subrows for each configuration all set to None, although the Debug/Release rows did list the proper profile/signing identity. Archiving in this state still gave me the error, until I explicitly set all the "Any iOS SDK" rows to their proper values.
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How to express a NOT IN query with ActiveRecord/Rails?
.... It would still break on nil, but I find that the array you pass in is usually generated by a filter that will return [] at the very least and never nil. I recommend checking out Squeel, a DSL on top of Active Record. Then you could do: Topic.where{id.not_in actions}, nil/empty/or otherwise.
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How to make a element expand or contract to its parent container?
...its parent container, in this case a <div> , no matter how big or small that container may be.
5 Answers
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Is delete this allowed?
Is it allowed to delete this; if the delete-statement is the last statement that will be executed on that instance of the class? Of course I'm sure that the object represented by the this -pointer is new ly-created.
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Get selected option from select element
...ted elements use
$("select option:selected").length
To Get the value of all selected elements use
var str = "";
$("select option:selected").each(function () {
str += $(this).text() + " ";
});
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Python: How to ignore an exception and proceed? [duplicate]
I have a try...except block in my code and When an exception is throw. I really just want to continue with the code because in that case, everything is still able to run just fine. The problem is if you leave the except: block empty or with a #do nothing, it gives you a syntax error. I can't use con...
Remove directory which is not empty
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There is a module for this called rimraf (https://npmjs.org/package/rimraf). It provides the same functionality as rm -Rf
Async usage:
var rimraf = require("rimraf");
rimraf("/some/directory", function () { console.log("done"); });
Sync usage:
rimr...
When should I use a composite index?
...olumn_A )
But it will not (at least not directly, maybe it can help partially if there are no better indices) help for queries that need
index( column_A, column_C )
Notice how column_B is missing.
In your original example, a composite index for two dimensions will mostly benefit queries that q...
how to remove untracked files in Git?
...y files, that you havn't thought of at first. Please double check and read all the comments below this answer and the --help section, etc., so to know all details to fine-tune your commands and surely get the expected result.
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