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How can I determine if a variable is 'undefined' or 'null'?
...enceError and break execution if variable is not defined or referred to at all in the code, using typeof is safer.
– Mani Gandham
Jun 15 '14 at 9:49
59
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What SOAP client libraries exist for Python, and where is the documentation for them? [closed]
... I'm doing this to get myself acquainted with both technologies. I've installed SOAPlib and I've tried to read their Client documentation, but I don't understand it too well. Is there anything else I can look into which is more suited for being a SOAP Client library for Python?
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Why is the minimalist, example Haskell quicksort not a “true” quicksort?
... two beautiful aspects:
Divide and conquer: break the problem into two smaller problems.
Partition the elements in-place.
The short Haskell example demonstrates (1), but not (2). How (2) is done may not be obvious if you don't already know the technique!
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Xcode stuck at “Your application is being uploaded”
... just keep your head cool and check this first method:
Check if your firewall protection is off. If not then turn it off. It maybe blocking you to connect your computer with iTunes
Store.
Try a different internet connection. The purpose for trying a different internet connection is that your curre...
How to get device make and model on iOS?
... if I have an iPhone 3GS vs. and iPhone 4 vs. an iPhone 4S (in actuality, all I really want to do is determine if I have a 3G or not, because I'm doing fairly graphics intensive stuff) .
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Finding duplicate values in a SQL table
...ly group on both of the columns.
Note: the older ANSI standard is to have all non-aggregated columns in the GROUP BY but this has changed with the idea of "functional dependency":
In relational database theory, a functional dependency is a constraint between two sets of attributes in a relation...
Find difference between timestamps in seconds in PostgreSQL
...
Try:
SELECT EXTRACT(EPOCH FROM (timestamp_B - timestamp_A))
FROM TableA
Details here: EXTRACT.
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How to loop through an associative array and get the key? [duplicate]
... using PHP 5, you should avoid using foreach by reference values and since all foreaches use internal array pointer ( current($Array) ) nesting foreaches or using PHP array functions can do weird things.
– Chaoix
Jul 12 '19 at 15:13
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Pandas: drop a level from a multi-level column index?
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@yoonghm It is there, you are probably just calling it on columns that don't have a multi-index
– matt harrison
Dec 18 '18 at 14:59
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PHP Fatal error: Call to undefined function json_decode()
Apache is logging PHP Fatal error: Call to undefined function json_decode() . After some googling, it seems this problem is a result of not having the latest version of php. Oddly, running php --version ouputs
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