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What is the default value for enum variable?
...
It is whatever member of the enumeration represents the value 0. Specifically, from the documentation:
The default value of an enum E is the value produced by the expression (E)0.
As an example, take the following enum:
enum E
{
Foo, Bar, Baz, Quux
}
Without overriding the ...
Add subdomain to localhost URL
...en (as root) the file /etc/hosts and add a line (or lines) like this:
127.0.0.1 example.com
127.0.0.1 subdomain.example.com
Your computer will now treat both example.com and subdomain.example.com as belonging to itself. If you visit either in your web browser, they will work the same, in pr...
SQL Server 2008 Windows Auth Login Error: The login is from an untrusted domain
When attempting to connect to a SQL Server 2008 Instance using Management Studio, I get the following error:
35 Answers
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Why does multiprocessing use only a single core after I import numpy?
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150
After some more googling I found the answer here.
It turns out that certain Python modules (num...
Change one value based on another value in pandas
... for you.
import pandas
df = pandas.read_csv("test.csv")
df.loc[df.ID == 103, 'FirstName'] = "Matt"
df.loc[df.ID == 103, 'LastName'] = "Jones"
As mentioned in the comments, you can also do the assignment to both columns in one shot:
df.loc[df.ID == 103, ['FirstName', 'LastName']] = 'Matt', 'Jone...
How do I write a “tab” in Python?
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Drew Dormann
47.5k1111 gold badges101101 silver badges153153 bronze badges
answered Dec 20 '10 at 10:07
SimoneSimone
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Unique (non-repeating) random numbers in O(1)?
I'd like to generate unique random numbers between 0 and 1000 that never repeat (i.e. 6 doesn't show up twice), but that doesn't resort to something like an O(N) search of previous values to do it. Is this possible?
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Efficient way to determine number of digits in an integer
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107
Well, the most efficient way, presuming you know the size of the integer, would be a lookup. S...
Efficiently test if a port is open on Linux?
...o use:
exec 6<>/dev/tcp/ip.addr.of.server/445
echo -e "GET / HTTP/1.0\n" >&6
cat <&6
I'm using 6 as the file descriptor because 0,1,2 are stdin, stdout, and stderr. 5 is sometimes used by Bash for child processes, so 3,4,6,7,8, and 9 should be safe.
As per the comment below, ...
How to suppress scientific notation when printing float values?
...%f' % (x/y)
but you need to manage precision yourself. e.g.,
'%f' % (1/10**8)
will display zeros only.
details are in the docs
Or for Python 3 the equivalent old formatting or the newer style formatting
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