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How do I know if a generator is empty from the start?
...lity only. def next(self): """Return the next message in a one-time iteration.""" if not hasattr(self, '_onetime_keys'): self._onetime_keys = self.iterkeys() while True: try: return self[next(self._onetime_keys)] except ...
How do I get a string format of the current date time, in python?
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You can use the datetime module for working with dates and times in Python. The strftime method allows you to produce string representation of dates and times with a format you specify.
>>> import datetime
>>> datetime.date.t...
Possible reasons for timeout when trying to access EC2 instance
I cannot SSH into my instance - Operation timed out. What could be the reasons why, and what can I do to resolve it? Rebooting normally takes a long time to take effect, and might just makes things worst
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Difference between declaring variables before or in loop?
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Well I ran your A and B examples 20 times each, looping 100 million times.(JVM - 1.5.0)
A: average execution time: .074 sec
B: average execution time : .067 sec
To my surprise B was slightly faster.
As fast as computers are now its hard to say if you could a...
How do I find Waldo with Mathematica?
...tion of 'useful'.) (This reminds me of some of the things iPhoto will sometimes identify as a face in our photo collection...)
– Brett Champion
Dec 12 '11 at 20:21
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How do Python functions handle the types of the parameters that you pass in?
... name in Python can perfectly well refer to different objects at different times (as in most programming languages, though not all) -- and there is no constraint on the name such that, if it has once referred to an object of type X, it's then forevermore constrained to refer only to other objects of...
Reshaping data.frame from wide to long format
...,
v.names = "Value",
idvar = c("Code", "Country"),
timevar = "Year",
times = 1950:1954)
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How can I measure the speed of code written in PHP? [closed]
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You have (at least) two solutions :
The quite "naïve" one is using microtime(true) tobefore and after a portion of code, to get how much time has passed during its execution ; other answers said that and gave examples already, so I won"t say much more.
This is a nice solution if you want to benc...
How to use NULL or empty string in SQL
I would like to know how to use NULL and an empty string at the same time in a WHERE clause in SQL Server. I need to find records that have either null values or an empty string. Thanks.
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Client-server synchronization pattern / algorithm?
... copy from master to detail, deltas and performance be damned. It's a one-time thing; the client is broken; don't try to optimize this, just implement a reliable copy.
Client is suspicious. In this case, you need to compare client against server to determine if the client is up-to-date and needs a...