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No Persistence provider for EntityManager named
...name using TopLink under the META-INF directory.
Then, I have my code calling it with:
30 Answers
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Polymorphism vs Overriding vs Overloading
...xample when teaching a class. The canonical "Bank Account" class didn't really express the "abstractness" of the base class. The other canonical example (Animal, make noise) was too abstract for understanding. I was looking for a single base with too obvious subclasses. Actually, goPee() was the...
JavaScript URL Decode function
...f I'm not mistaken, this is decoding + as %20, not as space - that's not really what you wanted here, is it? You'd want the space, not another version of an encoded character... no?
– Chris Moschini
Mar 1 '13 at 9:09
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Extract date (yyyy/mm/dd) from a timestamp in PostgreSQL
...swered May 26 '11 at 2:40
James AllmanJames Allman
37.4k99 gold badges5252 silver badges6969 bronze badges
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What does default(object); do in C#?
... value
For Nullable<T> it returns the empty (pseudo-null) value (actually, this is a re-statement of the first bullet, but it is worth making it explicit)
The biggest use of default(T) is in generics, and things like the Try... pattern:
bool TryGetValue(out T value) {
if(NoDataIsAvailab...
Bootstrap datepicker hide after selection
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I would recommend additionally checking if current view mode is 'days' : if (ev.viewMode === 'days') {$(this).datepicker('hide');} as you probably don't want to hide datepicker after selecting a month or a year}
– turan
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Check for current Node Version
I need to programmatically access the current node version running in a library I am writing. Can't seem to find this in the docs.
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How to list only top level directories in Python?
...use:
os.walk('.').next()[1]
How this works
os.walk is a generator and calling next will get the first result in the form of a 3-tuple (dirpath, dirnames, filenames). Thus the [1] index returns only the dirnames from that tuple.
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How to select the row with the maximum value in each group
...ata.table) ## 1.9.2
group <- as.data.table(group)
If you want to keep all the entries corresponding to max values of pt within each group:
group[group[, .I[pt == max(pt)], by=Subject]$V1]
# Subject pt Event
# 1: 1 5 2
# 2: 2 17 2
# 3: 3 5 2
If you'd like ju...
Get the key corresponding to the minimum value within a dictionary
...f two different keys have the same value? and they happen to both be the smallest value? how can you make it return both?
– user3226932
Dec 18 '16 at 4:29
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