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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(...
Why did my Git repo enter a detached HEAD state?
...t 2.23 (August 2019), you don't have to use the confusing git checkout command anymore.
git switch can also checkout a branch, and get a detach HEAD, except:
it has an explicit --detach option
To check out commit HEAD~3 for temporary inspection or experiment without creating a new branch:
g...
When should I use double instead of decimal?
...ing to offer at least as great precision (someone correct me if I'm wrong) and definitely greater speed for arbitrary real numbers. The simple conclusion is: when considering which to use, always use double unless you need the base 10 accuracy that decimal offers.
Edit:
Regarding your additional q...
How to do an INNER JOIN on multiple columns
I'm working on a homework project and I'm supposed to perform a database query which finds flights either by the city name or the airport code, but the flights table only contains the airport codes so if I want to search by city I have to join on the airports table.
...
How to convert JSON to CSV format and store in a variable
...ead it. Is there a way to convert this data using JavaScript in CSV format and save it in JavaScript file?
16 Answers
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Foreign key constraints: When to use ON UPDATE and ON DELETE
...ma using MySQL Workbench, which is pretty cool because you can do diagrams and it converts them :P
3 Answers
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UITableViewCell Separator disappearing in iOS7
...
I dumped the subview hierarchy of affected cells and found that the _UITableViewCellSeparatorView was set to hidden. No wonder it's not shown!
I overrode layoutSubviews in my UITableViewCell subclass and now the separators are displayed reliably:
Objective-C:
- (void)lay...
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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Getting java.lang.ClassNotFoundException: org.apache.commons.logging.LogFactory exception
...& getting this exception.
I have already included common-logging1.1.1.jar and spring.jar file. Could you please help to out?
...
What is the difference between JOIN and JOIN FETCH when using JPA and Hibernate
Please help me understand where to use a regular JOIN and where a JOIN FETCH.
5 Answers
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