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Why does Python code run faster in a function?
...to PyPy, up to the current version (1.8 at the time of this writing.) The test code from the OP runs about four times slower in global scope compared to inside a function.
– GDorn
Jun 28 '12 at 17:17
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Learning Python from Ruby; Differences and Similarities
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[x*x for x in values if x > 15]
to get a new list of the squares of all values greater than 15. In Ruby, you'd have to write the following:
values.select {|v| v > 15}.map {|v| v * v}
The Ruby code doesn't feel as compact. It's also not as efficient since it first converts the values a...
Python logging: use milliseconds in time format
...d of a struct_time, then (at least with modern versions of Python) we can call ct.strftime and then we can use %f to format microseconds:
import logging
import datetime as dt
class MyFormatter(logging.Formatter):
converter=dt.datetime.fromtimestamp
def formatTime(self, record, datefmt=None...
Is there a way for multiple processes to share a listening socket?
...POSIX type OS), using fork() will cause the forked child to have copies of all the parent's file descriptors. Any that it does not close will continue to be shared, and (for example with a TCP listening socket) can be used to accept() new sockets for clients. This is how many servers, including Apac...
How to detect that animation has ended on UITableView beginUpdates/endUpdates?
...ates . I am also using beginUpdates/endUpdates when adjusting rowHeight. All these operations are animated by default.
7 ...
How to properly seed random number generator
...roduce a given sequence (which is usually only done for debugging and unit testing).
After that you simply call Intn to get the next random integer.
Move the rand.Seed(time.Now().UTC().UnixNano()) line from the randInt function to the start of the main and everything will be faster.
Note also tha...
How to fix java.lang.UnsupportedClassVersionError: Unsupported major.minor version
...ings. Then select Compiler Compliance Level to 1.7, 1.6 or 1.5, build and test your app.
– Vivek Kumar Ray
Aug 16 '13 at 9:55
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How do I force a UITextView to scroll to the top every time I change the text?
...ge with location:0, length:0, worked. My text view was not editable, and I tested both selectable and not selectable (neither setting affected the result). Here's a Swift example:
myTextView.text = "Text that is long enough to scroll"
myTextView.scrollRangeToVisible(NSRange(location:0, length:0))
...
Adding new column to existing DataFrame in Python pandas
... because if you have multiple rows, and you use the assignment, it assigns all rows of the new column with that value ( in your case e) which is usually undesirable.
– Paniz
Apr 27 '19 at 22:42
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Is there a NumPy function to return the first index of something in an array?
...:
itemindex = numpy.where(array==item)
The result is a tuple with first all the row indices, then all the column indices.
For example, if an array is two dimensions and it contained your item at two locations then
array[itemindex[0][0]][itemindex[1][0]]
would be equal to your item and so woul...