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Determine the number of NA values in a column
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Thank you for this. To em>x m>pand this a little bit. In counting amount of arbitrary value, other than NA is writing a boolean function is.value and then using sum(is.value(df$col)) the way to go or is there a more concise direct syntam>x m> for this?
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Test if em>x m>ecutable em>x m>ists in Python?
In Python, is there a portable and simple way to test if an em>x m>ecutable program em>x m>ists?
21 Answers
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Why can't C++ be parsed with a LR(1) parser?
...n of C++ parsing, which states that:
"C++ grammar is ambiguous,
contem>x m>t-dependent and potentially
requires infinite lookahead to resolve
some ambiguities".
It goes on to give a number of em>x m>amples (see page 147 of the pdf).
The em>x m>ample is:
int(m>x m>), y, *const z;
meaning
int m>x m>;
int y;
i...
JQuery: 'Uncaught TypeError: Illegal invocation' at ajam>x m> request - several elements
...ar data = {
'mode': 'filter_city',
'id_A': e[e.selectedIndem>x m>]
};
it should be:
var data = {
'mode': 'filter_city',
'id_A': e[e.selectedIndem>x m>].value
};
Note: check Jason Kulatunga's answer, it quotes JQuery doc to em>x m>plain why passing an HTML element was causing tr...
Adding a parameter to the URL with JavaScript
In a web application that makes use of AJAm>X m> calls, I need to submit a request but add a parameter to the end of the URL, for em>x m>ample:
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Which is the fastest algorithm to find prime numbers?
... and square free operations, both operations being of about the same complem>x m>ity and able to be optimized in about the same way.
– GordonBGood
Dec 6 '13 at 3:06
7
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Iteration ng-repeat only m>X m> times in AngularJs
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Angular comes with a limitTo:limit filter, it support limiting first m>x m> items and last m>x m> items:
<div ng-repeat="item in items|limitTo:4">{{item}}</div>
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Validation failed for one or more entities while saving changes to SQL Server Database using Entity
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You can em>x m>tract all the information from the DbEntityValidationEm>x m>ception with the following code (you need to add the namespaces: System.Data.Entity.Validation and System.Diagnostics to your using list):
catch (DbEntityValidationEm>x m>ce...
How to post pictures to instagram using API
...because they should provide one. I am not sure if there is any other way (em>x m>cept the apps for android and iOS) to upload picture using php. Kindly give me any sort of idea if there is any possibility.
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What is duck typing?
...ong typing.
The idea is that you don't need a type in order to invoke an em>x m>isting method on an object - if a method is defined on it, you can invoke it.
The name comes from the phrase "If it looks like a duck and quacks like a duck, it's a duck".
Wikipedia has much more information.
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