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Append a dictionary to a dictionary [duplicate]
...is used as keyword argument for the dict constructor. The constructor will then copy the values from this argument into itself. So you create an additional dictionary with dict(**orig). This is wasteful when the dictionaries are big, as in the original question.
– Martin Geisle...
How to update PATH variable permanently from Windows command line?
... set PATH=%PATH%;C:\\Something\\bin from the command line ( cmd.exe ) and then execute echo %PATH% I see this string added to the PATH. If I close and open the command line, that new string is not in PATH.
...
How to drop columns by name in a data frame
...:8)
R> df
x y z u
1 1 2 3 4
2 2 3 4 5
3 3 4 5 6
4 4 5 6 7
5 5 6 7 8
Then you can use the which function and the - operator in column indexation :
R> df[ , -which(names(df) %in% c("z","u"))]
x y
1 1 2
2 2 3
3 3 4
4 4 5
5 5 6
Or, much simpler, use the select argument of the subset funct...
What does the git index contain EXACTLY?
...-1 repositories, we use SHA-1 and in SHA-256 repositories, we use SHA-256, then replace all other uses of "SHA-1" with something more neutral.
Avoid referring to "160-bit" hash values.
technical/index-format now includes in its man page:
All binary numbers are in network byte order.
In a repositor...
select and update database record with a single queryset
... Just a fair warning... if you use the update method like this then any signals attached to that model or other "code stuff" won't run against the objects. Just a pointer from someone who got burned :)
– DMac the Destroyer
Jan 26 '12 at 6:01
...
Generate pdf from HTML in div using Javascript
...o ignore certain elements, you have to mark them with an ID, which you can then ignore in a special element handler of jsPDF. Therefore your HTML should look like this:
<!DOCTYPE html>
<html>
<body>
<p id="ignorePDF">don't print this to pdf</p>
<div>
...
How do I make a Mac Terminal pop-up/alert? Applescript?
...es, you can. :) However you need to be logged in. e.g by terminal ssh. and then invoke osascript -e 'display dialog "Hello!"'
– Alex Reds
Jun 10 '14 at 23:53
...
How do I move a file with Ruby?
...o ended up having trouble with FileUtils.mv, which would move the file and then say it didn't have permission to delete the old file. I ended up using FileUtils.cp and then File.delete to get rid of the old file.
– d3vkit
Jan 25 '13 at 11:27
...
How to populate/instantiate a C# array with a single value?
...d to verify my belief: If the return value of i++ isn't used for anything, then the compiler will compile it as ++i automatically for you. Also, even when I do use the return value, the performance difference is so small I needed to make an extreme case in order to measure it. Even then, it resulted...
CHECK constraint in MySQL is not working
...ustomer
-> FOR EACH ROW
-> BEGIN
-> IF NEW.SD<0 THEN
-> SET NEW.SD=0;
-> END IF;
-> END
-> //
mysql> delimiter ;
Hope that helps.
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