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Should I use a data.frame or a matrix?
...mine the choice.
Also:
Matrices are more memory efficient:
m = matrix(1:4, 2, 2)
d = as.data.frame(m)
object.size(m)
# 216 bytes
object.size(d)
# 792 bytes
Matrices are a necessity if you plan to do any linear algebra-type of operations.
Data frames are more convenient if you frequently refer ...
What are the differences between poll and select?
... the comments
in the system header imply today) but it takes more work. 4.4BSD's
kernel and the Solaris library function both have this limit. But I
see that BSD/OS 2.1 has now been coded to avoid this limit, so it's
doable, just a small matter of programming. :-) Someone should file a
...
Does it make any sense to use inline keyword with templates?
...x2.cc:(.text+0x0): multiple definition of `int g<int>(int)'
/tmp/ccUa4K20.o:inlinexx.cc:(.text+0x0): first defined here
collect2: ld returned 1 exit status
Not stating inline when doing explicit instantiation may also lead to issues.
So in summary: For non fully specialized function templat...
What is the smallest possible valid PDF?
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4 Answers
4
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What kind of leaks does automatic reference counting in Objective-C not prevent or minimize?
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edited Oct 8 '18 at 14:13
answered Jun 17 '11 at 16:11
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Java - No enclosing instance of type Foo is accessible
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487
static class Thing will make your program work.
As it is, you've got Thing as an inner class,...
What do (lambda) function closures capture?
...ers[i] = (lambda b: lambda a: b + a)(i)
...
>>> adders[1](3)
4
>>> adders[2](3)
5
The scope here is created using a new function (a lambda, for brevity), which binds its argument, and passing the value you want to bind as the argument. In real code, though, you most likely w...
Why do I need Transaction in Hibernate for read-only operations?
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4 Answers
4
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How to find duplicates in 2 columns not 1
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194
You should set up a composite key between the two fields. This will require a unique stone_id a...