大约有 47,000 项符合查询结果（耗时：0.0494秒） [XML]
Creating an empty list in Python
...how you can test which piece of code is faster:
% python -mtimeit "l=[]"
10000000 loops, best of 3: 0.0711 usec per loop
% python -mtimeit "l=list()"
1000000 loops, best of 3: 0.297 usec per loop
However, in practice, this initialization is most likely an extremely small part of your program, ...
Kill process by name?
...
answered May 31 '10 at 0:50
Alex MartelliAlex Martelli
725k148148 gold badges11261126 silver badges13241324 bronze badges
...
#ifdef in C#
...
answered Jun 10 '09 at 12:50
heavydheavyd
15.9k55 gold badges5353 silver badges6969 bronze badges
...
How to get different colored lines for different plots in a single figure?
...
E.g.:
import matplotlib.pyplot as plt
import numpy as np
x = np.arange(10)
plt.plot(x, x)
plt.plot(x, 2 * x)
plt.plot(x, 3 * x)
plt.plot(x, 4 * x)
plt.show()
And, as you may already know, you can easily add a legend:
import matplotlib.pyplot as plt
import numpy as np
x = np.arange(10)
pl...
bash HISTSIZE vs. HISTFILESIZE?
...Long answer:
All the info above + some examples:
Example 1:
HISTFILESIZE=10 and HISTSIZE=10
You start your session.
Your HISTFILE (file that stores your bash command history), is truncated to contain HISTFILESIZE=10 lines.
You write 50 lines.
At the end of your 50 commands, only commands 41 to...
How to detect modifier key states in WPF?
...
answered Apr 21 '11 at 23:10
Kyrylo MKyrylo M
10.4k66 gold badges4343 silver badges7171 bronze badges
...
Conditions for automatic generation of default/copy/move ctor and copy/move assignment operator?
...ator or destructor, and if the generated move constructor is valid (§12.8/10).
The move assignment operator is auto-generated if there is no user-declared copy constructor, copy assignment operator or destructor, and if the generated move assignment operator is valid (e.g. if it wouldn't need to as...
Is short-circuiting logical operators mandated? And evaluation order?
...
answered Mar 10 '09 at 0:37
Alex BAlex B
73.5k3636 gold badges187187 silver badges270270 bronze badges
...
How to check status of PostgreSQL server Mac OS X
...et something like this:
$ show-pg-status
pg_ctl: server is running (PID: 11030)
/usr/local/Cellar/postgresql/9.2.4/bin/postgres
share
|
improve this answer
|
follow
...
Does JavaScript have “Short-circuit” evaluation?
...
+100
This answer goes into great detail on how short-circuiting works in JavaScript, with all the gotcha's and also relevant themes such ...