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Unique Constraint in Entity Framework Code First
... constraint is one thing you can't enforce with code alone. You can dramatically reduce the probability of a violation in code (by checking uniqueness prior to calling SaveChanges()), but there's still the possibility of another insert/update slipping in between the time of the uniqueness check and ...
how to draw directed graphs using networkx in python?
...if edge not in red_edges]
# Need to create a layout when doing
# separate calls to draw nodes and edges
pos = nx.spring_layout(G)
nx.draw_networkx_nodes(G, pos, cmap=plt.get_cmap('jet'),
node_color = values, node_size = 500)
nx.draw_networkx_labels(G, pos)
nx.draw_networkx_e...
Make a program run slowly
...wer the priority using nice (and/or renice). You can also do it programmatically using nice() system call. This will not slow down the execution speed per se, but will make Linux scheduler allocate less (and possibly shorter) execution time frames, preempt more often, etc. See Process Scheduling (Ch...
Hidden Features of ASP.NET [closed]
...son most people don't know them. I am asking for features that are not typically taught by the text books.
53 Answers
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Unicode (UTF-8) reading and writing to files in Python
...o
>>>f = io.open("test", mode="r", encoding="utf-8")
Then after calling f's read() function, an encoded Unicode object is returned.
>>>f.read()
u'Capit\xe1l\n\n'
Note that in Python 3, the io.open function is an alias for the built-in open function. The built-in open function ...
why is plotting with Matplotlib so slow?
...xample up.
There are two main reasons why this is as slow as it is.
1) Calling fig.canvas.draw() redraws everything. It's your bottleneck. In your case, you don't need to re-draw things like the axes boundaries, tick labels, etc.
2) In your case, there are a lot of subplots with a lot of tic...
How can I reliably determine the type of a variable that is declared using var at design time?
...ontaining the interesting expression. We start by transforming it syntactically to
var z = y.Where(foo=>foo.
In order to work out the type of foo we must first know the type of y. So at this point we ask the type determiner "what is the type of y"? It then starts up an expression evaluator w...
What is a deadlock?
...
I'm using process here as a generalisation, not specifically an OS Process. These could be threads, but could also be completely different applications, or database connections. The pattern is the same.
– Keith
Sep 23 '08 at 14:42
...
Android: TextView: Remove spacing and padding on top and bottom
...etIncludeFontPadding (boolean includepad)
or in XML this would be:
android:includeFontPadding="false"
Set whether the TextView includes extra top and bottom padding to make room for accents that go above the normal ascent and descent. The default is true.
...
What is thread safe or non-thread safe in PHP?
...P web server supports multiple models for handling requests, one of which (called the worker MPM) uses threads. But it supports another concurrency model called the prefork MPM which uses processes -- that is, the web server will create/dedicate a single process for each request.
There are also oth...