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How to JSON serialize sets?
...ng dict.fromkeys(s) then you lose the ability to recover dictionaries).
A more sophisticated solution is to build-out a custom type that can coexist with other native JSON types. This lets you store nested structures that include lists, sets, dicts, decimals, datetime objects, etc.:
from json imp...
What does .SD stand for in data.table in R
.... There's no significance to the initial ".", except that it makes it even more unlikely that there will be a clash with a user-defined column name.
If this is your data.table:
DT = data.table(x=rep(c("a","b","c"),each=2), y=c(1,3), v=1:6)
setkey(DT, y)
DT
# x y v
# 1: a 1 1
# 2: b 1 3
# 3: c 1...
How to move an element into another element?
...ing how people still think jQuery equals JavaScript. No need for jQuery anymore in 2017, really.
– nkkollaw
Sep 7 '17 at 22:17
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promise already under evaluation: recursive default argument reference or earlier problems?
...ke test<- function(g.=g, T=1, f..=f){ g.(1,T, f.=f..) }? In cases with more recursions, is it a good and safe practice adding more .? (2) if f is a non-function argument, for example g <- function(x, T, f=f){ exp(-fx/T) }* and test<- function(g.=g, T=1, f=f){ g.(1,T, f=f.) }, will using t...
Should I use static_cast or reinterpret_cast when casting a void* to whatever
...ress.
This is a reason to prefer static_cast.
Additionally, and arguably more important, is the fact that every use of reinterpret_cast is downright dangerous because it converts anything to anything else really (for pointers), while static_cast is much more restrictive, thus providing a better le...
Find string between two substrings [duplicate]
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MySQL offset infinite rows
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Terrible! they need to get more elegant than that... Limit -1 or Limit Null looks pretty reasonable! or atleast Limit should accept a subquery like select * from table limit (select count(*) from table)
– vulcan raven
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Rails find_or_create_by more than one attribute?
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How do you convert Html to plain text?
...ry about <script> tags and the like then you'll need something a bit more powerful then regular expressions because you need to track state, omething more like a Context Free Grammar (CFG). Althought you might be able to accomplish it with 'Left To Right' or non-greedy matching.
If you can us...
How does a Breadth-First Search work when looking for Shortest Path?
...ining distance then how would we know the shortest distance,please explain more.
– Gaurav Sehgal
Apr 12 '15 at 19:17
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