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Is returning by rvalue reference more efficient?
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Beta_ab&&
Beta::toAB() const {
return move(Beta_ab(1, 1));
}
This returns a dangling reference, just like with the lvalue reference case. After the function returns, the temporary object will get destructed. You should return Beta_ab by value, like the following
Beta_ab...
Opposite of %in%: exclude rows with values specified in a vector
A categorical variable V1 in a data frame D1 can have values represented by the letters from A to Z. I want to create a subset D2, which excludes some values, say, B, N and T. Basically, I want a command which is the opposite of %in%
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dyld: Library not loaded: /usr/local/lib/libpng16.16.dylib with anything php related
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What is the function of the DBMDL File in VS database project
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1 Answer
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Open the file in universal-newline mode using the CSV Django module
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How to use mysql JOIN without ON condition?
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155
MySQL documentation covers this topic.
Here is a synopsis. When using join or inner join, th...
Copy multiple files in Python
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139
You can use os.listdir() to get the files in the source directory, os.path.isfile() to see if ...
Postgres: Distinct but only for one column
I have a table on pgsql with names (having more than 1 mio. rows), but I have also many duplicates. I select 3 fields: id , name , metadata .
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Entity Framework select distinct name
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271
Using lambda expression..
var result = EFContext.TestAddresses.Select(m => m.Name).Distinct...
time.sleep — sleeps thread or process?
...Thread
class worker(Thread):
def run(self):
for x in xrange(0,11):
print x
time.sleep(1)
class waiter(Thread):
def run(self):
for x in xrange(100,103):
print x
time.sleep(5)
def run():
worker().start()
waiter().start(...