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How do we control web page caching, across all browsers?
...he correct minimum set of headers that works across all mentioned clients (and proxies):
Cache-Control: no-cache, no-store, must-revalidate
Pragma: no-cache
Expires: 0
The Cache-Control is per the HTTP 1.1 spec for clients and proxies (and implicitly required by some clients next to Expires). The...
How to make lists contain only distinct element in Python? [duplicate]
...g aspect of this new implementation is considered an implementation detail and should not be relied upon". Since they're both based on hashes, I'd think set would be the same, but it's not mentioned, so apparently not: docs.python.org/3.6/whatsnew/3.6.html
– Mark
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Redis strings vs Redis hashes to represent JSON: efficiency?
...e cases):
Store the entire object as JSON-encoded string in a single key and keep track of all Objects using a set (or list, if more appropriate). For example:
INCR id:users
SET user:{id} '{"name":"Fred","age":25}'
SADD users {id}
Generally speaking, this is probably the best method in most cas...
Replace all 0 values to NA
...ays in ?'NULL',
NULL represents the null object in R
which is unique and, I guess, can be seen as the most uninformative and empty object.1 Then it becomes not so surprising that
data.frame(x = c(1, NULL, 2))
# x
# 1 1
# 2 2
That is, R does not reserve any space for this null object.2 Mea...
How to format numbers? [duplicate]
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I wanted to use built in code and this got me there. The locales options is a small issue I'm willing to live with. I think this should be the accepted answer because it takes into account the locale nuances of number rendition.
– A...
What is the difference between print and puts?
For example in this line of code I wrote, print and puts produce different results.
6 Answers
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How to reshape data from long to wide format
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+1 and you don't need to rely on external packages, since reshape comes with stats. Not to mention that it's faster! =)
– aL3xa
May 5 '11 at 0:07
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Red black tree over avl tree
AVL and Red black trees are both self-balancing except Red and black color in the nodes. What's the main reason for choosing Red black trees instead of AVL trees? What are the applications of Red black trees?
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In Matlab, when is it optimal to use bsxfun?
...ng
Using bsxfun, like using accumarray, makes me feel good about my understanding of Matlab.
bsxfun will replicate the input arrays along their "singleton dimensions", i.e. the dimensions along which the size of the array is 1, so that they match the size of the corresponding dimension of the othe...
What is the meaning of “POSIX”?
What is POSIX? I have read the Wikipedia article and I read it every time I encounter the term. The fact is that I never really understood what it is.
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