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Reading a huge .csv file
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You are reading all rows into a list, then processing that list. Don't do that.
Process your rows as you produce them. If you need to filter the data first, use a generator function:
import csv
def getstuff(filename, criterion):
with ...
How to log a method's execution time exactly in milliseconds?
...ed for being a bad example. See also the related answer that explains this all in more detail: stackoverflow.com/a/30363702/43615
– Thomas Tempelmann
Jun 4 '16 at 13:36
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Super-simple example of C# observer/observable with delegates
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The observer pattern is usually implemented with events.
Here's an example:
using System;
class Observable
{
public event EventHandler SomethingHappened;
public void DoSomething() =>
SomethingHappened?.Invoke(this, EventArgs.Empt...
Python Sets vs Lists
...move the object creation now. The setup phase of the timeit loops is only called once (docs.python.org/2/library/timeit.html#timeit.Timer.timeit).
– Ellis Percival
Sep 30 '14 at 10:09
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Is there a way to crack the password on an Excel VBA Project?
...y best to explain how it works - please excuse my English.
The VBE will call a system function to create the password dialog box.
If user enters the right password and click OK, this function returns 1. If user enters the wrong password or click Cancel, this function returns 0.
After the dialog bo...
Catch a thread's exception in the caller thread in Python
I'm very new to Python and multithreaded programming in general. Basically, I have a script that will copy files to another location. I would like this to be placed in another thread so I can output .... to indicate that the script is still running.
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Callback functions in C++
In C++, when and how do you use a callback function?
10 Answers
10
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Is it possible to specify your own distance function using scikit-learn K-Means Clustering?
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Here's a small kmeans that uses any of the 20-odd distances in
scipy.spatial.distance, or a user function.
Comments would be welcome (this has had only one user so far, not enough);
in particular, what are your N, dim, k, metric ?
#!/u...
Can “using” with more than one resource cause a resource leak?
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No.
The compiler will generate a separate finally block for each variable.
The spec (§8.13) says:
When a resource-acquisition takes the form of a
local-variable-declaration, it is possible to acquire multiple
resources of a given type. A using statement of the...
How to detect iPhone 5 (widescreen devices)?
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First of all, you shouldn't rebuild all your views to fit a new screen, nor use different views for different screen sizes.
Use the auto-resizing capabilities of iOS, so your views can adjust, and adapt any screen size.
That's not v...