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Pandas - Get first row value of a given column
...oc[0] = x affects df_test, but df_test.iloc[0]['Btime']
may not. See below for an explanation of why. Because a subtle difference in
the order of indexing makes a big difference in behavior, it is better to use single indexing assignment:
df.iloc[0, df.columns.get_loc('Btime')] = x
df.iloc[0, ...
Equivalent C++ to Python generator pattern
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Generators exist in C++, just under another name: Input Iterators. For example, reading from std::cin is similar to having a generator of char.
You simply need to understand what a generator does:
there is a blob of data: the local variables define a state
there is an init method
there is...
How to read the database table name of a Model instance?
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Found the answer myself: the _meta attribute of an instance has the information:
model_instance._meta.db_table
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Django 1.7 throws django.core.exceptions.AppRegistryNotReady: Models aren't loaded yet
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This is what solved it for us and these folks:
Our project started with Django 1.4, we went to 1.5 and then to 1.7. Our wsgi.py looked like this:
import os
from django.core.handlers.wsgi import WSGIHandler
os.environ['DJANGO_SETTINGS_MODULE'] =...
What difference is there between WebClient and HTTPWebRequest classes in .NET?
...traction built on top of HttpWebRequest to simplify the most common tasks. For instance, if you want to get the content out of an HttpWebResponse, you have to read from the response stream:
var http = (HttpWebRequest)WebRequest.Create("http://example.com");
var response = http.GetResponse();
var s...
How to check Django version
I have to use Python and Django for our application. So I have two versions of Python, 2.6 and 2.7. Now I have installed Django. I could run the sample application for testing Django succesfuly. But how do I make sure whether Django uses the 2.6 or 2.7 version and what version of modules Django ...
How to implement the factory method pattern in C++ correctly
There's this one thing in C++ which has been making me feel uncomfortable for quite a long time, because I honestly don't know how to do it, even though it sounds simple:
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See changes to a specific file using git
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Use a command like:
git diff file_2.rb
See the git diff documentation for full information on the kinds of things you can get differences for.
Normally, git diff by itself shows all the changes in the whole repository (not just the current directory).
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MySQL: Sort GROUP_CONCAT values
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Your code is heavily relied upon for your specific answer, and therefore should not be placed anywhere but your original post. If you put it here in this comment, many programmers here won't see it, and you won't get the best possible response :)
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UICollectionView current visible cell index
... get
- (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView{
for (UICollectionViewCell *cell in [self.mainImageCollection visibleCells]) {
NSIndexPath *indexPath = [self.mainImageCollection indexPathForCell:cell];
NSLog(@"%@",indexPath);
}
}
Update to Swift 5:
fu...