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How to reshape data from long to wide format
...s this simply, with gather()/spread() being the terms for melt/cast.
Edit: Now, in 2019, tidyr v 1.0 has launched and set spread and gather on a deprecation path, preferring instead pivot_wider and pivot_longer, which you can find described in this answer. Read on if you want a brief glimpse into th...
Unable to generate an explicit migration in entity framework
...ith proper startup project, so everything worked fine. But this is logical now - b/c EF takes connection string from the project, thus it "does not know" that migrations actually already applied to DB...
– kosist
May 15 at 21:12
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Check if PHP session has already started
... really think about refactoring your session management code if you don't know whether or not a session is started...
That said, my opinion is subjective, and there are situations (examples of which are described in the comments below) where it may not be possible to know if the session is started....
How to use the IEqualityComparer
...nting interfaces of classes it is important to read the documentation, to know which contract you’re supposed to implement.1
In your code, the solution is to forward GetHashCode to Class_reglement.Numf.GetHashCode and implement it appropriately there.
Apart from that, your Equals method is full ...
Adjust UILabel height to text
...want to adjust their height to the text, this is the code I wrote for this now
17 Answers
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Why do we always prefer using parameters in SQL statements?
I am very new to working with databases. Now I can write SELECT , UPDATE , DELETE , and INSERT commands. But I have seen many forums where we prefer to write:
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Django templates: verbose version of a choice
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yes, I know. It's not as general (universal), though - unless you know a way to iterate in a template over all get_FOO_display methods of a model object :) I'm a bit too lazy for writing non-generic templates ;) Moreover, the docs ...
SqlAlchemy - Filtering by Relationship Attribute
...ives you filtering/sorting with "magical" strings as in Django, so you can now write something like
Patient.where(mother___phenoscore=10)
It's a lot shorter, especially for complex filters, say,
Comment.where(post___public=True, post___user___name__like='Bi%')
Hope you will enjoy this package
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Check orientation on Android phone
...g ALWAYS. If you think about a moment, this is exactly what you want - to know if width is smaller than height (portrait), the opposite (landscape) or if they are the same (square).
Then it comes down to this simple code:
public int getScreenOrientation()
{
Display getOrient = getWindowManag...
Passing Data between View Controllers
...elf didFinishEnteringItem:itemToPassBack];
That's it for ViewControllerB. Now in ViewControllerA.h, tell ViewControllerA to import ViewControllerB and conform to its protocol.
#import "ViewControllerB.h"
@interface ViewControllerA : UIViewController <ViewControllerBDelegate>
In ViewControl...