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Delete everything in a MongoDB database
...very single collection, and whatever else might be lying around, and start from scratch. Is there a single line of code that will let me do this? Bonus points for giving both a MongoDB console method and a MongoDB Ruby driver method.
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Converting SVG to PNG using C# [closed]
...plemented - I checked the source code. @FrankHale I had to remove an xmlns from the svg because raphael added it twice.
– fireydude
Oct 30 '13 at 10:24
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In Flux architecture, how do you manage Store lifecycle?
... and decoupled as possible -- a self-contained universe that one can query from a Controller-View. The only road into the Store is through the callback it registers with the Dispatcher. The only road out is through getter functions. Stores also publish an event when their state has changed, so Co...
How do you calculate the average of a set of circular data? [closed]
...erage of a set of circular data. For example, I might have several samples from the reading of a compass. The problem of course is how to deal with the wraparound. The same algorithm might be useful for a clockface.
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How to set a Django model field's default value to a function call / callable (e.g., a date relative
...u are not defining a function, so function default values are irrelevant:
from datetime import datetime, timedelta
class MyModel(models.Model):
# default to 1 day from now
my_date = models.DateTimeField(default=datetime.now() + timedelta(days=1))
This last line is not defining a function; it ...
How to automatically generate a stacktrace when my program crashes
...ws the load module, offset, and function that each frame in the stack came from. Here you can see the signal handler on top of the stack, and the libc functions before main in addition to main, foo, bar, and baz.
share
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When to use in vs ref vs out
... b are. If the call goes to a server in Hawaii, copying the initial values from here to Hawaii is a waste of bandwidth. A similar snippet using ref:
string a = String.Empty, b = String.Empty;
person.GetBothNames(ref a, ref b);
could confuse readers, because it looks like the initial values of a a...
How do you get the current project directory from C# code when creating a custom MSBuild task?
... Besides that, you can use the Visual Studio SDK and get the location from the solution configuration layout using DTE2.
– Latency
Nov 29 '18 at 16:41
2
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C++ auto keyword. Why is it magic?
From all the material I used to learn C++, auto has always been a weird storage duration specifier that didn't serve any purpose. But just recently, I encountered code that used it as a type name in and of itself. Out of curiosity I tried it, and it assumes the type of whatever I happen to assig...
When saving, how can you check if a field has changed?
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I use following mixin:
from django.forms.models import model_to_dict
class ModelDiffMixin(object):
"""
A model mixin that tracks model fields' values and provide some useful api
to know what fields have been changed.
"""
def ...