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Why dict.get(key) instead of dict[key]?
...ide a default value if the key is missing:
dictionary.get("bogus", default_value)
returns default_value (whatever you choose it to be), whereas
dictionary["bogus"]
would raise a KeyError.
If omitted, default_value is None, such that
dictionary.get("bogus") # <-- No default specified --...
How do you 'redo' changes after 'undo' with Emacs?
...
To undo: C-_
To redo after a undo: C-g C-_
Type multiple times on C-_ to redo what have been undone by C-_
To redo an emacs command multiple times, execute your command then type C-xz and then type many times on z key to repea...
How can I create a unique constraint on my column (SQL Server 2008 R2)?
...
Or set column as unique from the SQL Query window:
alter table location_key drop constraint pinky;
alter table your_table add constraint pinky unique(yourcolumn);
Changes take effect immediately:
Command(s) completed successfully.
...
How to dynamically create a class?
...rtyType)
{
FieldBuilder fieldBuilder = tb.DefineField("_" + propertyName, propertyType, FieldAttributes.Private);
PropertyBuilder propertyBuilder = tb.DefineProperty(propertyName, PropertyAttributes.HasDefault, propertyType, null);
MethodBuilder getPropMt...
How do I include a pipe | in my linux find -exec command?
...o use your top level shell to perform the piping like so:
find -name 'file_*' -follow -type f -exec zcat {} \; | agrep -dEOE 'grep'
In terms of efficiency this results costs one invocation of find, numerous invocations of zcat, and one invocation of agrep.
This would result in only a single agre...
Find out time it took for a python script to complete execution
...test function"
L = []
for i in range(100):
L.append(i)
if __name__=='__main__':
from timeit import Timer
t = Timer("test()", "from __main__ import test")
print t.timeit()
Then to convert to minutes, you can simply divide by 60. If you want the script runtime in an easi...
Rename Files and Directories (Add Prefix)
...ll work for filenames with spaces in them:
for f in * ; do mv -- "$f" "PRE_$f" ; done
("--" is needed to succeed with files that begin with dashes, whose names would otherwise be interpreted as switches for the mv command)
...
Why does sys.exit() not exit when called inside a thread in Python?
...from the thread?
Apart from the method Deestan described you can call os._exit (notice the underscore). Before using it make sure that you understand that it does no cleanups (like calling __del__ or similar).
share
...
How to throw std::exceptions with variable messages?
...atter & operator << (const Type & value)
{
stream_ << value;
return *this;
}
std::string str() const { return stream_.str(); }
operator std::string () const { return stream_.str(); }
enum ConvertToString
{
to_str
};...
Share Large, Read-Only Numpy Array Between Multiprocessing Processes
...n
from multiprocessing import Process
import sharedmem
import numpy
def do_work(data, start):
data[start] = 0;
def split_work(num):
n = 20
width = n/num
shared = sharedmem.empty(n)
shared[:] = numpy.random.rand(1, n)[0]
print "values are %s" % shared
processes = [Proc...