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Unable to load DLL 'SQLite.Interop.dll'
Periodically I am getting the following exception:
41 Answers
41
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Checking for empty arrays: count vs empty
...s simply that something that should have happened, didn't happen: the non-existence of the member variable in the subclass was treated exactly the same way as though this member variable, an array, was empty — i.e., as though it had no elements). This is problematic, and another example of PHP bei...
How to concatenate twice with the C preprocessor and expand a macro as in “arg ## _ ## MACRO”?
...
Standard C Preprocessor
$ cat xx.c
#define VARIABLE 3
#define PASTER(x,y) x ## _ ## y
#define EVALUATOR(x,y) PASTER(x,y)
#define NAME(fun) EVALUATOR(fun, VARIABLE)
extern void NAME(mine)(char *x);
$ gcc -E xx.c
# 1 "xx.c"
# 1 "<built-in>"
# 1 "<...
What's the fastest way to merge/join data.frames in R?
For example (not sure if most representative example though):
5 Answers
5
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How do you match only valid roman numerals with a regular expression?
...hinking about my other problem , i decided I can't even create a regular expression that will match roman numerals (let alone a context-free grammar that will generate them)
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How to convert strings into integers in Python?
...ins lists, only one level), you could do this in Python 2:
T2 = [map(int, x) for x in T1]
In Python 3:
T2 = [list(map(int, x)) for x in T1]
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“var” or no “var” in JavaScript's “for-in” loop?
...s I show here. First, there is this approach where the iteration variable x is explicitly declared:
9 Answers
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How to convert a factor to integer\numeric without loss of information?
...nd may
happen by implicit coercion. To
transform a factor f to
approximately its original numeric
values, as.numeric(levels(f))[f] is
recommended and slightly more
efficient than
as.numeric(as.character(f)).
The FAQ on R has similar advice.
Why is as.numeric(levels(f))[f] more ef...
How does Dijkstra's Algorithm and A-Star compare?
... we only consider the distance from the source right? And the minimum vertex is taken into consideration?
– Kraken
Apr 26 '13 at 22:18
5
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How to suppress “unused parameter” warnings in C?
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I usually write a macro like this:
#define UNUSED(x) (void)(x)
You can use this macro for all your unused parameters. (Note that this works on any compiler.)
For example:
void f(int x) {
UNUSED(x);
...
}
...