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Difference between CLOB and BLOB from DB2 and Oracle Perspective?
...contain mixed-width characters. Binary objects are possibly non-printable. All character is binary, the converse is not necessarily true once you leave the database, nor again when leaving the platform.
– mckenzm
Apr 21 '16 at 5:18
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Count number of objects in list [closed]
...'s put some stuff in it - 3 components/indexes/tags (whatever you want to call it) each with differing amounts of elements:
> mylist <- list(record1=c(1:10),record2=c(1:5),record3=c(1:2))
If you are interested in just the number of components in a list use:
> length(mylist)
[1] 3
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What is the difference between HashSet and List?
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Actually, I prefer the answer that points out that HashSets are suitable in cases that you can treat your collection as "bag items". Set operations are not so frequent as Containment checks. At any point that you have a set of un...
R object identification
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I usually start out with some combination of:
typeof(obj)
class(obj)
sapply(obj, class)
sapply(obj, attributes)
attributes(obj)
names(obj)
as appropriate based on what's revealed. For example, try with:
obj <- data.frame(a...
JavaScript - cannot set property of undefined
...initializer:
d[a] = {
greetings: b,
data: c
};
Or you could set all the properties of d in an anonymous function instance:
d = new function () {
this[a] = {
greetings: b,
data: c
};
};
If you're in an environment that supports ES2015 features, you can use comp...
Rounding DateTime objects
...clear in your initial spec.
How you want boundary cases to round.
normally only an issue if you are rounding to the middle rather than the end.
Since rounding to the middle is an attempt at a bias free answer you need to use something like Bankers Rounding technically round half even to be trul...
How do malloc() and free() work?
I want to know how malloc and free work.
13 Answers
13
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Mapping two integers to one, in a unique and deterministic way
...d for e.g. dovetailing. Have a look at this PDF for an introduction to so-called pairing functions. Wikipedia introduces a specific pairing function, namely the Cantor pairing function:
Three remarks:
As others have made clear, if you plan to implement a pairing function, you may soon find you ...
new DateTime() vs default(DateTime)
...al.
default(), for any value type (DateTime is a value type) will always call the parameterless constructor.
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Numpy array assignment with copy
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All three versions do different things:
B = A
This binds a new name B to the existing object already named A. Afterwards they refer to the same object, so if you modify one in place, you'll see the change through the other...