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Convert unix time to readable date in pandas dataframe

...12.15 3 1349979305 12.19 4 1350065705 12.15 In [25]: df['date'] = pd.to_datetime(df['date'],unit='s') In [26]: df.head() Out[26]: date price 0 2012-10-08 18:15:05 12.08 1 2012-10-09 18:15:05 12.35 2 2012-10-10 18:15:05 12.15 3 2012-10-11 18:15:05 12.19 4 2012-10-12 18:15:...
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Anonymous recursive PHP functions

... pass it by reference. Be aware, that if you modify the $factorial before calling the function, the result will change as it's passed by reference. – Marius Balčytis Sep 13 '12 at 21:48 ...
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Why is Scala's immutable Set not covariant in its type?

...ameter of type A due to the contravariance of functions. Set could potentially be contravariant in A, but this too causes issues when you want to do things like this: def elements: Iterable[A] In short, the best solution is to keep things invariant, even for the immutable data structure. You'll...
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Cast Object to Generic Type for returning

...> T convertInstanceOfObject(java.lang.Object); Code: 0: aload_0 1: areturn 2: astore_1 3: aconst_null 4: areturn Exception table: from to target type 0 1 2 Class java/lang/ClassCastException public static void main(java...
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Thread Safety in Python's dictionary

...mic operations, there are corner cases where they aren’t atomic (e.g. if __hash__ or __eq__ are implemented as Python methods) and their atomicity should not be relied upon. Neither should you rely on atomic variable assignment (since this in turn depends on dictionaries). Use the Queue module's Q...
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Delete files older than 10 days using shell script in Unix [duplicate]

... these! Once, using a command very much like this in a cron job, I accidentally deleted every file on my production mail server older than 10 days, which I can tell you was no fun to recover from. – DSimon May 28 '14 at 20:00 ...
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Global access to Rake DSL methods is deprecated

... You can "delete" Rake 0.9.1 by running the following command: gem uninstall rake -v=0.9.1 If you have multiple versions of the gem installed, you'll be prompted to pick a version. After 0.9.1 was cleaned out, I ran bundle update rake and was finally able to create my database files. I was ...
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Separation of business logic and data access in django

...de is confusing and, after a certain time, I cease to understand what is really happening. 10 Answers ...
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How to access object attribute given string corresponding to name of that attribute

...ay prefer to use a generalized getter method like so: class Test: def __init__(self): self.attr1 = 1 self.attr2 = 2 def get(self,varname): return getattr(self,varname) t = Test() x = "attr1" print ("Attribute value of {0} is {1}".format(x, t.get(x))) Outputs: At...
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Proper way to use AJAX Post in jquery to pass model from strongly typed MVC3 view

... Nothing glaring stands out as a security issue to me. If you're really concerned about it though, you can always make a custom model binder on the mvc side. – Craig M May 12 '11 at 18:31 ...