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python list by value not by reference [duplicate]
Let's take an em>x m>ample
11 Answers
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quick random row selection in Postgres
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You might want to em>x m>periment with OFFSET, as in
SELECT myid FROM mytable OFFSET floor(random()*N) LIMIT 1;
The N is the number of rows in mytable. You may need to first do a SELECT COUNT(*) to figure out the value of N.
Update (by Antony Hat...
Renaming or copying files and folder using NERDTree on Vim. Is it possible?
I checked the documentation and I couldn't find a way o renaming or copying files and folder using NERDTree. Is it possible?
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How to save a plot as image on the disk?
... pdf() or similar
Plot your model
Close the device using dev.off()
Some em>x m>ample code for saving the plot to a png file:
fit <- lm(some ~ model)
png(filename="your/file/location/name.png")
plot(fit)
dev.off()
This is described in the (combined) help page for the graphical formats ?png, ?bmp,...
Why not infer template parameter from constructor?
my question today is pretty simple: why can't the compiler infer template parameters from class constructors, much as it can do from function parameters? For em>x m>ample, why couldn't the following code be valid:
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Unable to load DLL (Module could not be found HRESULT: 0m>x m>8007007E)
...C:\windows\system32 or c:\windows\SysWOW64 (for 32-bit process on 64-bit bom>x m>).
Reading from the Path environment variable
In addition I'd check the dependencies of the DLL, the dependency walker provided with Visual Studio can help you out here, it can also be downloaded for free: http://www.depen...
GIT commit as different user without email / or only email
I'm trying to commit some changes as a different user, but i do not have a valid email address, following command is not working for me:
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Remove trailing zeros
I have some fields returned by a collection as
18 Answers
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How do I check if a number evaluates to infinity?
...finity property isn't read-only which means that it can be redefined: For em>x m>ample, var m>x m> = 42; Infinity = 42; alert(m>x m> === Infinity); displays "true". (Admittedly that's an obscure case, and anyone who decides to redefine Infinity, NaN etc should em>x m>pect odd things to happen.)
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Remove duplicate elements from array in Ruby
... no, the uniq! method will return nil if the array had been unique yet Em>x m>: a = [1,2,3,4] a.uniq -> [1,2,3,4] but a.uniq! -> nil
– duykhoa
Apr 4 '13 at 8:37
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