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Cleanest way to get last item from Python iterator
What's the best way of getting the last item from an iterator in Python 2.6? For example, say
14 Answers
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Is gettimeofday() guaranteed to be of microsecond resolution?
I am porting a game, that was originally written for the Win32 API, to Linux (well, porting the OS X port of the Win32 port to Linux).
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Can I query MongoDB ObjectId by date?
...Briefly in JavaScript code:
/* This function returns an ObjectId embedded with a given datetime */
/* Accepts both Date object and string input */
function objectIdWithTimestamp(timestamp) {
/* Convert string date to Date object (otherwise assume timestamp is a date) */
if (typeof(timestamp...
How do you round to 1 decimal place in Javascript?
...ar rounded = Math.round(number * 10) / 10
// rounded is 12.3
if you want it to have one decimal place, even when that would be a 0, then add...
var fixed = rounded.toFixed(1)
// fixed is always to 1 d.p.
// NOTE: .toFixed() returns a string!
// To convert back to number format
parseFloat(number....
Programmatically obtain the Android API level of a device?
... can run some piece of code which requires newer API in the following way (it will execute if the current device's API level is at least 4)
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.DONUT) {
}
To obtain user visible Android Version use:
Build.VERSION.RELEASE
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How to add an extra column to a NumPy array
...timings:
In [23]: N = 10
In [24]: a = np.random.rand(N,N)
In [25]: %timeit b = np.hstack((a,np.zeros((a.shape[0],1))))
10000 loops, best of 3: 19.6 us per loop
In [27]: %timeit b = np.zeros((a.shape[0],a.shape[1]+1)); b[:,:-1] = a
100000 loops, best of 3: 5.62 us per loop
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What does `:_*` (colon underscore star) do in Scala?
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It "splats"1 the sequence.
Look at the constructor signature
new Elem(prefix: String, label: String, attributes: MetaData, scope: NamespaceBinding,
child: Node*)
which is called as
new Elem(prefix, label, attrib...
What is the purpose of double curly braces in React's JSX syntax?
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It's just an object literal inlined in the prop value. It's the same as
var obj = {__html: rawMarkup};
<span dangerouslySetInnerHTML={obj} />
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Patterns for handling batch operations in REST web services?
What proven design patterns exist for batch operations on resources within a REST style web service?
8 Answers
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Selecting a row of pandas series/dataframe by integer index
...ndas-docs/stable/indexing.html
Here we have new operators, .iloc to explicity support only integer indexing, and .loc to explicity support only label indexing
e.g. imagine this scenario
In [1]: df = pd.DataFrame(np.random.rand(5,2),index=range(0,10,2),columns=list('AB'))
In [2]: df
Out[2]:
...