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What's the yield keyword in JavaScript?
...O.
The function containing the yield keyword is a generator. When you call it, its formal parameters are bound to actual arguments, but its body isn't actually evaluated. Instead, a generator-iterator is returned. Each call to the generator-iterator's next() method performs another pass through ...
Insert, on duplicate update in PostgreSQL?
...it would be much slower, because each upsert would be its' own individual call into the database.
– baash05
Mar 1 '12 at 0:27
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How do I print a double value with full precision using cout?
...
Is the really the right answer? When I manually use a high number, I can print out as many as 51 digits of approximated e, but with cout.precision(numeric_limits<double>::digits10 + 2); I only get 16....
– ...
Can I use git diff on untracked files?
...The upshot is that your "untracked" file now becomes a modification to add all the content to this zero-length file, and that shows up in the "git diff" output.
git diff
echo "this is a new file" > new.txt
git diff
git add -N new.txt
git diff
diff --git a/new.txt b/new.txt
index e69de29..3b2ae...
Using pg_dump to only get insert statements from one table within database
I'm looking for a way to get all rows as INSERT statements from one specific table within a database using pg_dump in PostgreSQL.
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How to 'bulk update' with Django?
...ings like incrementing rows:
from django.db.models import F
Entry.objects.all().update(n_pingbacks=F('n_pingbacks') + 1)
See the documentation.
However, note that:
This won't use ModelClass.save method (so if you have some logic inside it won't be triggered).
No django signals will be emitte...
How do I add the contents of an iterable to a set?
What is the "one [...] obvious way" to add all items of an iterable to an existing set ?
6 Answers
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Installing SciPy with pip
It is possible to install NumPy with pip using pip install numpy .
15 Answers
15...
Is it possible to implement a Python for range loop without an iterator variable?
...ed by Ryan. It can mess up your interpreter.
>>> for _ in xrange(10): pass
...
>>> _
9
>>> 1+2
3
>>> _
9
And according to Python grammar, it is an acceptable variable name:
identifier ::= (letter|"_") (letter | digit | "_")*
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When saving, how can you check if a field has changed?
...models/…
– Colonel Sponsz
Aug 30 '10 at 19:55
10
@callum so that if you make changes to the obj...