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When should I use @classmethod and when def method(self)?
...fine functions in classes. The author seems to use them both very intentionally. The first one is one I myself use a lot:
3...
Why use make over a shell script?
...t would be a lot more work (explicitly checking the last-modified dates on all the files, etc.) The only obvious alternative with a shell script is to rebuild everything every time. For tiny projects this is a perfectly reasonable approach, but for a big project a complete rebuild could easily take ...
Replacing blank values (white space) with NaN in pandas
I want to find all values in a Pandas dataframe that contain whitespace (any arbitrary amount) and replace those values with NaNs.
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JavaScript isset() equivalent
...
I generally use the typeof operator:
if (typeof obj.foo !== 'undefined') {
// your code here
}
It will return "undefined" either if the property doesn't exist or its value is undefined.
(See also: Difference between undefi...
How to sort a HashMap in Java [duplicate]
...tion order (which I often like for debugging), or by access order. And finally if you're doing a lot of this you might check out Java 1.6 and NavigableMap, awesome stuff!
– Mark Bennett
Jan 5 '12 at 0:58
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Django using get_user_model vs settings.AUTH_USER_MODEL
...s.AUTH_USER_MODEL will delay the retrieval of the actual model class until all apps are loaded. get_user_model will attempt to retrieve the model class at the moment your app is imported the first time.
get_user_model cannot guarantee that the User model is already loaded into the app cache. It mi...
Determine which MySQL configuration file is being used
...inux, then start the 'mysqld' with strace, for eg strace ./mysqld.
Among all the other system calls, you will find something like:
stat64("/etc/my.cnf", 0xbfa3d7fc) = -1 ENOENT (No such file or directory)
stat64("/etc/mysql/my.cnf", {st_mode=S_IFREG|0644, st_size=4227, ...}) = 0
open("/etc/...
Moment js date time comparison
...hen use:
moment(theStringToParse).utc()
Or perhaps you don't need it at all. Just because the input value is in UTC, doesn't mean you have to work in UTC throughout your function.
You seem to be getting the "now" instance by moment(new Date()). You can instead just use moment().
Updated
Bas...
Getting exact error type in from DbValidationException
...ity.Validation.DbEntityValidationResult} which gives me no information at all about what field it was unable to initialize.
Is there a way to get more info about this error?
...
Horizontal ListView in Android?
Is it possible to make the ListView horizontally? I have done this using a gallery view, but the selected item comes to the center of the screen automatically. I don't want the selected item at the same spot I clicked. How can I rectify this problem? My idea was to set the ListView with a horizo...