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How to format a java.sql Timestamp for displaying?
...er that if SimpleDateFormat object is a local-scoped object (it is created and used only inside a method), then it is thread-safe, since stack on which it will reside is inherently "thread-safe" (as it belongs to a single thread).
– quantum
Sep 13 '11 at 9:52
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Can existing virtualenv be upgraded gracefully?
I have a virtualenv created for Python 2.5 and want to "upgrade" it to Python 2.6.
5 Answers
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surface plots in matplotlib
...ing projection='3d' in add_subplot
import matplotlib.pyplot as plt
import random
def fun(x, y):
return x**2 + y
fig = plt.figure()
ax = fig.add_subplot(111, projection='3d')
x = y = np.arange(-3.0, 3.0, 0.05)
X, Y = np.meshgrid(x, y)
zs = np.array(fun(np.ravel(X), np.ravel(Y)))
Z = zs.reshape(...
Re-entrant locks in C#
...g on the same object. The recursive code effectively already has the lock and so can continue unhindered.
lock(object) {...} is shorthand for using the Monitor class. As Marc points out, Monitor allows re-entrancy, so repeated attempts to lock on an object on which the current thread already has ...
Get the current year in JavaScript
...
Create a new Date() object and call getFullYear():
new Date().getFullYear()
// returns the current year
Hijacking the accepted answer to provide some basic example context like a footer that always shows the current year:
<footer>
&...
How to get the browser viewport dimensions?
...
Cross-browser @media (width) and @media (height) values
const vw = Math.max(document.documentElement.clientWidth || 0, window.innerWidth || 0)
const vh = Math.max(document.documentElement.clientHeight || 0, window.innerHeight || 0)
window.innerWidth a...
Why am I suddenly getting a “Blocked loading mixed active content” issue in Firefox?
...visits a page served over HTTP, their connection is open for eavesdropping and man-in-the-middle (MITM) attacks. When a user visits a page served over HTTPS, their connection with the web server is authenticated and encrypted with SSL and hence safeguarded from eavesdroppers and MITM attacks.
Howeve...
Map a network drive to be used by a service
Suppose some Windows service uses code that wants mapped network drives and no UNC paths. How can I make the drive mapping available to the service's session when the service is started? Logging in as the service user and creating a persistent mapping will not establish the mapping in the context of...
How to check if an array field contains a unique value or another array in MongoDB?
...n the help: mongodb.org/display/DOCS/…
– Scott Hernandez
Mar 20 '11 at 4:31
2
for the $all does...
NewLine in object summary
...E, the above "solution" actually displays a lone BLANK LINE between line 1 and line 2 (that is, a newline after line 1 followed by a blank line then line 2)--this is not the same a new line, as the OP requested. Is that a bug in the VS 2017 IDE--or does everyone who up-voted not see that this answer...