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In practice, what are the main uses for the new “yield from” syntax in Python 3.3?
...or v in g: yield v does not even begin to do justice to what yield from is all about. Because, let's face it, if all yield from does is expand the for loop, then it does not warrant adding yield from to the language and preclude a whole bunch of new features from being implemented in Python 2.x.
Wh...
Why doesn't Python have a sign function?
... it wasn't accepted, because they didn't agree on what it should return in all the edge cases (+/-0, +/-nan, etc)
So they decided to implement only copysign, which (although more verbose) can be used to delegate to the end user the desired behavior for edge cases - which sometimes might require the...
How to pad zeroes to a string?
...)) # or
print('{0:05d}'.format(number)) # or (explicit 0th positional arg. selection)
print('{n:05d}'.format(n=number)) # or (explicit `n` keyword arg. selection)
print(format(number, '05d'))
Documentation for string formatting and f-strings.
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Shared-memory objects in multiprocessing
... some other parameters). func with different parameters can be run in parallel. For example:
4 Answers
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Filling a DataSet or DataTable from a LINQ query result set
...order.Field<DateTime>("OrderDate") > new DateTime(2001, 8, 1)
select order;
// Create a table from the query.
DataTable boundTable = query.CopyToDataTable<DataRow>();
Why won't that work for you?
share
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Most efficient way of making an if-elif-elif-else statement when the else is done the most?
...ere an example of a if with dynamic conditions translated to a dictionary.
selector = {lambda d: datetime(2014, 12, 31) >= d : 'before2015',
lambda d: datetime(2015, 1, 1) <= d < datetime(2016, 1, 1): 'year2015',
lambda d: datetime(2016, 1, 1) <= d < datetime(2...
SQL DELETE with INNER JOIN
...d = n.idTemplate
WHERE n.type = "monster";
It might be a better idea to select the rows before deleting so you are sure your deleting what you wish to:
SELECT * FROM spawnlist
INNER JOIN npc ON spawnlist.npc_templateid = npc.idTemplate
WHERE npc.type = "monster";
You can also check the MySQL d...
Does Foreign Key improve query performance?
...the foreign key relationship already inforces that for you.
So this:
select p.ProductId, p.Name, c.CategoryId, c.Name AS Category
from Products p inner join ProductCategories c on p.CategoryId = c.CategoryIdwhere c.CategoryId = 1;
Becomes this:
SELECT p.ProductId, p.Name, c.CategoryId, c.N...
Get absolute path of initially run script
...tioning that, reading the documentation, there is no mention that the initially run script's path is the first item of the array returned by get_included_files(). I suggest to store __FILE__ into a constant at the beginning of the script meant to be initially run.
– Paolo
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Use of *args and **kwargs [duplicate]
...u're not sure how many arguments might be passed to your function, i.e. it allows you pass an arbitrary number of arguments to your function. For example:
>>> def print_everything(*args):
for count, thing in enumerate(args):
... print( '{0}. {1}'.format(count, thing))
...
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