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Determine the line of code that causes a segmentation fault?
...e tutorial to get you started with GDB.
Where the segfault occurs is generally only a clue as to where "the mistake which causes" it is in the code. The given location is not necessarily where the problem resides.
share
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Why does the expression 0 < 0 == 0 return False in Python?
...o say 0 < x <= 5 than to say (0 < x) and (x <= 5).
These are called chained comparisons. And that's a link to the documentation for them.
With the other cases you talk about, the parenthesis force one relational operator to be applied before the other, and so they are no longer chained...
Render HTML to PDF in Django site
...
Try the solution from Reportlab.
Download it and install it as usual with python setup.py install
You will also need to install the following modules: xhtml2pdf, html5lib, pypdf with easy_install.
Here is an usage example:
First define this function:
import cStringIO as Str...
How are feature_importances in RandomForestClassifier determined?
...d in [1] (often cited, but unfortunately rarely read...). It is sometimes called "gini importance" or "mean decrease impurity" and is defined as the total decrease in node impurity (weighted by the probability of reaching that node (which is approximated by the proportion of samples reaching that no...
What's the difference between __PRETTY_FUNCTION__, __FUNCTION__, __func__?
... = "function-name";
appeared, where function-name is the name of the lexically-enclosing function. This name is the unadorned name of the function.
Note that it is not a macro and it has no special meaning during preprocessing.
__func__ was added to C++ in C++11, where it is specified as containi...
What is the use of static variable in C#? When to use it? Why can't I declare the static variable in
...
A static variable shares the value of it among all instances of the class.
Example without declaring it static:
public class Variable
{
public int i = 5;
public void test()
{
i = i + 5;
Console.WriteLine(i);
}
}
public class Exercise
{
...
ObservableCollection not noticing when Item in it changes (even with INotifyPropertyChanged)
...
The ContentList's Set method will not get called when you change a value inside the collection, instead you should be looking out for the CollectionChanged event firing.
public class CollectionViewModel : ViewModelBase
{
public ObservableCollection<E...
What is the use of join() in Python threading?
...t clumsy ascii-art to demonstrate the mechanism:
The join() is presumably called by the main-thread. It could also be called by another thread, but would needlessly complicate the diagram.
join-calling should be placed in the track of the main-thread, but to express thread-relation and keep it as s...
What's the canonical way to check for type in Python?
...ation.
One more note: in this case, if you're using Python 2, you may actually want to use:
if isinstance(o, basestring):
because this will also catch Unicode strings (unicode is not a subclass of str; both str and unicode are subclasses of basestring). Note that basestring no longer exists in P...
Example for boost shared_mutex (multiple reads/one write)?
I have a multithreaded app that has to read some data often, and occasionally that data is updated. Right now a mutex keeps access to that data safe, but it's expensive because I would like multiple threads to be able to read simultaneously, and only lock them out when an update is needed (the updat...