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How can I explicitly free memory in Python?
... I'm using python 3.6. Calling gc.collect() after loading a pandas dataframe from hdf5 (500k rows) reduced memory usage from 1.7GB to 500MB
– John
Jan 18 '18 at 20:30
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How to check iOS version?
...lable(iOS 9, *) {}
In Objective-C, you need to check the system version and perform a comparison.
[[NSProcessInfo processInfo] operatingSystemVersion] in iOS 8 and above.
As of Xcode 9:
if (@available(iOS 9, *)) {}
The full answer …
In Objective-C, and Swift in rare cases, it's better to...
Measure and Benchmark Time for Ruby Methods
How can i measure the time taken by a method and the individual statements in that method in Ruby. If you see the below method i want to measure the total time taken by the method and the time taken for database access and redis access. I do not want to write Benchmark.measure before every statement...
How do I convert from int to Long in Java?
I keep finding both on here and Google people having troubles going from long to int and not the other way around. Yet I'm sure I'm not the only one that has run into this scenario before going from int to Long .
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UI Design Pattern for Windows Forms (like MVVM for WPF)
...ectly suited for it. But what about Windows Forms? Is there an established and commonly used approach / design pattern like this for Windows Forms too? One that works explicitly well with Windows Forms? Is there a book or an article that describes this well? Maybe MVP or MVC based?
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How do I add more members to my ENUM-type column in MySQL?
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Most ALTER TABLE commands will completely rewrite the whole table. Is mysql clever enough to not do that with enum ?
– John
Oct 9 '18 at 22:10
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Unable to simultaneously satisfy constraints, will attempt to recover by breaking constraint
Below is the error message I receive in the debug area. It runs fine and nothing is wrong except that I receive this error. Would this prevent apple accepting the app? How do I fix it?
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Go to particular revision
...repository of a certain project. Can I turn the files to the initial state and when I review the files go to revision 2, 3, 4 ... most recent? I'd like to have an overview of how the project was evolving.
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Remove empty space before cells in UITableView
...no scrolling has occurred. When the table is scrolled, the content scrolls and shows under a transparent navigation bar. This behavior is of course wanted only if the table view starts directly under the navigation bar, which is not the case here.
Another thing to note is that iOS adjusts the cont...
What does the NS prefix mean?
... code for the Cocoa frameworks came from the NeXTSTEP libraries Foundation and AppKit (those names are still used by Apple's Cocoa frameworks), and the NextStep engineers chose to prefix their symbols with NS.
Because Objective-C is an extension of C and thus doesn't have namespaces like in C++, sy...