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How to avoid isset() and empty()
... the E_NOTICE error level, because the existence of variables is not explicitly checked using isset() and consorts.
11 An...
What is the use of hashCode in Java?
... is the address of the element inside the set/map.
When you do contains() it will take the hash code of the element, then look for the bucket where hash code points to. If more than 1 element is found in the same bucket (multiple objects can have the same hash code), then it uses the equals() metho...
What's the fastest way to merge/join data.frames in R?
... and merge approaches are not the same. Match is, of course, faster since it is not doing as much. In particular it never looks for duplicate keys. (continued after code)
DF1 = data.frame(a = c(1, 1, 2, 2), b = 1:4)
DF2 = data.frame(b = c(1, 2, 3, 3, 4), c = letters[1:5])
merge(DF1, DF2)
b a c...
Create a unique number with javascript time
... creating a number using time. The number would be made up of the four digit year, two digit month, two digit day, two digit hour, two digit minute, two digit second, and three digit millisecond. So it would look something like this: 20111104103912732 ... this would give enough certainty of a uniq...
How does the Java 'for each' loop work?
...
for (Iterator<String> i = someIterable.iterator(); i.hasNext();) {
String item = i.next();
System.out.println(item);
}
Note that if you need to use i.remove(); in your loop, or access the actual iterator in some wa...
How to extract img src, title and alt from html using php? [duplicate]
I would like to create a page where all images which reside on my website are listed with title and alternative representation.
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Pretty-print an entire Pandas Series / DataFrame
I work with Series and DataFrames on the terminal a lot. The default __repr__ for a Series returns a reduced sample, with some head and tail values, but the rest missing.
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How can I search for a multiline pattern in a file?
...ring pattern. The first solution that comes to mind is using find piped with xargs grep :
11 Answers
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Security of REST authentication schemes
..., SSL alone is NOT a viable authentication mechanism for a REST API. SSL without client authc only authenticates the server, which is irrelevant for most REST APIs because you really want to authenticate the client.
If you don't use TLS client authentication, you'll need to use something like a ...
C++ template constructor
I wish to have a non-template class with a template constructor with no arguments.
8 Answers
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