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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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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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“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 to suppress “unused parameter” warnings in C?
...
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);
...
}
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Rounded UIView using CALayers - only some corners - How?
...class:
@interface MyView : UIImageView
{
}
I'd never used graphics contexts before, but I managed to hobble together this code. It's missing the code for two of the corners. If you read the code, you can see how I implemented this (by deleting some of the CGContextAddArc calls, and deleting some ...
How to update Python?
... in each of your conda environments to update all packages and the Python executable for that version. Also, since they changed their name to Anaconda, I don't know if the Windows registry keys are still the same.
UPDATE: 2017-03-24
There have been no updates to Python(x,y) since June of 2015, so ...
What is the optimal Jewish toenail cutting algorithm?
...es per foot*, so there are only 5! = 120 unrestricted sequences.
Python example:
#seq is only valid when consecutive elements in the list differ by at least two.
def isValid(seq):
for i in range(len(seq)-1):
a = seq[i]
b = seq[i+1]
if abs(a-b) == 1:
return ...
Define a lambda expression that raises an Exception
How can I write a lambda expression that's equivalent to:
6 Answers
6
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Are 2^n and n*2^n in the same time complexity?
Resources I've found on time complexity are unclear about when it is okay to ignore terms in a time complexity equation, specifically with non-polynomial examples.
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