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Why is iterating through a large Django QuerySet consuming massive amounts of memory?
...QuerySet in the following ways:
Iteration. A QuerySet is iterable, and it executes its database query the first time you iterate over it. For example, this will print the headline of all entries in the database:
for e in Entry.objects.all():
print e.headline
So your ten million ro...
Where to place AutoMapper.CreateMaps?
...nterface of words" - can't enforce it, but you expect it, so you can code (and refactor) if necessary.
EDIT:
Just thought I'd mention that I now use AutoMapper profiles, so the above example becomes:
public static class AutoMapperWebConfiguration
{
public static void Configure()
{
Map...
plot a circle with pyplot
...rcle with matplotlib.pyplot (please no pylab) taking as input center (x,y) and radius r. I tried some variants of this:
9 A...
Get most recent file in a directory on Linux
Looking for a command that will return the single most recent file in a directory.
21 Answers
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How many levels of pointers can we have?
...
The C standard specifies the lower limit:
5.2.4.1 Translation limits
276 The implementation shall be able to translate and execute at least one program that contains at least one instance of every one of the following limits...
What does PermGen actually stand for?
...n specific.
Briefly, it contains the Java objects associated with classes and interned strings. In Sun's client implementation with sharing on, classes.jsa is memory mapped to form the initial data, with about half read-only and half copy-on-write.
Java objects that are merely old are kept in the ...
How can I indent multiple lines in Xcode?
When I select multiple lines of code and want to indent them as usual with TAB key, it just deletes them all. I come from Eclipse where I always did it that way. How's that done in Xcode? I hope not line by line ;)
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Can I hide the HTML5 number input’s spin box?
...s the spin-button for webkit browsers (have tested it in Chrome 7.0.517.44 and Safari Version 5.0.2 (6533.18.5)):
input::-webkit-outer-spin-button,
input::-webkit-inner-spin-button {
/* display: none; <- Crashes Chrome on hover */
-webkit-appearance: none;
margin: 0; /* <-...
Test if characters are in a string
...
@GregSnow -- Tried system.time(a <- grepl("abc", vec)) and system.time(a <- grepl("abc", vec, fixed=TRUE)), and fixed=TRUE is still, if anything slightly slower. The difference isn't appreciable with these short strings, but fixed=TRUE still doesn't seem to be faster. Thanks ...
How do I reset the scale/zoom of a web app on an orientation change on the iPhone?
When I start my app in portrait mode, it works fine. Then I rotate into landscape and it's scaled up. To get it to scale correctly for the landscape mode I have to double tap on something twice, first to zoom all the way in (the normal double tap behavior) and again to zoom all the way out (again, ...