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How to delete an item in a list if it exists?
...d catch relevant Exceptions:
try:
some_list.remove(thing)
except ValueError:
pass # or scream: thing not in some_list!
except AttributeError:
call_security("some_list not quacking like a list!")
Off course the second except clause in the example above is not only of questionable humor...
How do I get current date/time on the Windows command line in a suitable format for usage in a file/
...- snip -- snip ----------8<-------------
To get the code to work sans error msg's to stderr, I had to add the single quotes arount the variable assignments for %%a, %%b and %%c. My locale (PT) was causing errors at one stage in the looping/parsing where stuff like "set =20" was getting execute...
How do I plot in real-time in a while loop using matplotlib?
...ange(10):
y = np.random.random()
plt.scatter(i, y)
plt.pause(0.05)
plt.show()
Note some of the changes:
Call plt.pause(0.05) to both draw the new data and it runs the GUI's event loop (allowing for mouse interaction).
...
Entity framework linq query Include() multiple children entities
...xt node (NB: This does NOT work with AsNoTracking() - you'll get a runtime error):
var company = context.Companies
.Include(co =>
co.Employees
.Select(emp => emp.Employee_Car
.Select(ec => ec.Employee)
.Select(e...
What would be C++ limitations compared C language? [closed]
...D_POSIX_C_SOURCE=200112L -Wall -Wextra -Wwrite-strings -Wredundant-decls -Werror -Isrc src/core/kin_object.c -c -o obj/kin_object.o | wc -l
In file included from src/core/kin_object.c:22:
src/core/kin_object.h:791:28: error: anonymous variadic macros were introduced in C99
In file included from src...
Check if an apt-get package is installed and then install it if it's not on Linux
...s upon finding that the package is missing, such as simply exiting with an error code.
REQUIRED_PKG="some-package"
PKG_OK=$(dpkg-query -W --showformat='${Status}\n' $REQUIRED_PKG|grep "install ok installed")
echo Checking for $REQUIRED_PKG: $PKG_OK
if [ "" = "$PKG_OK" ]; then
echo "No $REQUIRED_P...
How to run a shell script in OS X by double-clicking?
... you'll see the following symptoms:
.command: Finder displays a misleading error message that suggests the problem can be fixed via File > Get Info, which is not true - use the chmod +x method suggested above.
no suffix:
with a shebang line (e.g., #!/bin/bash): behavior is as if the suffix wer...
How to enumerate a range of numbers starting at 1
... is straightforward to do in Python 2.6 or newer:
enumerate(range(2000, 2005), 1)
Python 2.5 and older do not support the start parameter so instead you could create two range objects and zip them:
r = xrange(2000, 2005)
r2 = xrange(1, len(r) + 1)
h = zip(r2, r)
print h
Result:
[(1, 2000), (...
linux: kill background task
... job. If a prefix matches more than one job, bash
reports an error. Using %?ce, on the other hand, refers to any job containing the string ce in its command line. If the
substring matches more than one job, bash reports an error. The symbols %% and %+ refer to the shell's n...
Explicitly select items from a list or tuple
... recent call last):
File "<stdin>", line 1, in <module>
IndexError: invalid index
>>> myBigList[[87, 342, 217, 998, 500]]
array([ 87, 342, 217, 998, 500])
>>> myBigList[numpy.array([87, 342, 217, 998, 500])]
array([ 87, 342, 217, 998, 500])
The tuple doesn't work th...