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How to check if a value exists in a dictionary (python)
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it wasn't necesarry after all, unless run on bigger dict. I guess overhead in values() is caused by copying the value list and in viewvalues() by maintaining the view alive.
– soulcheck
Nov 21 '11 at 17:12
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Convert a float64 to an int in Go
...problem in Go that can be unexpected (at least if you come from Java): "In all non-constant conversions involving floating-point or complex values, if the result type cannot represent the value the conversion succeeds but the result value is implementation-dependent." (golang.org/ref/spec#Conversion...
How to profile methods in Scala?
What is a standard way of profiling Scala method calls?
12 Answers
12
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OpenCV C++/Obj-C: Detecting a sheet of paper / Square Detection
...e I was unable to find a relevant implementation I decided to accept the challenge.
I made some modifications to the squares demo present in OpenCV and the resulting C++ code below is able to detect a sheet of paper in the image:
void find_squares(Mat& image, vector<vector<Point> >...
Team Build Error: The Path … is already mapped to workspace
...ity TF - Team Foundation Version Control Tool (tf).
You can get a list of all workspaces by bringing up a Visual Studio Command Prompt then changing to your workspace folder and issuing the following commands:
C:\YourWorkspaceFolder>tf workspaces /owner:*
You should see your problem workspace...
LINQ: Distinct values
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Oh so by "larger type" you may mean I still want all properties in the result even though I only want to compare a few properties to determine distinctness?
– The Red Pea
Sep 20 '16 at 14:31
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How to create a GUID/UUID using iOS
...tring = CFUUIDCreateString(NULL, theUUID);
CFRelease(theUUID);
return (__bridge NSString *)string;
}
EDIT: Jan, 29 2014:
If you're targeting iOS 6 or later, you can now use the much simpler method:
NSString *UUID = [[NSUUID UUID] UUIDString];
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What does |= (ior) do in Python?
...s1 |= s2 # 2
>>> s1.__ior__(s2) # 3
where the final value of s1 is equivalent either by:
an assigned OR operation
an in-place OR operation
an in-place OR operation via special method++
Example
Here we a...
what is reverse() in Django
...!-- django <= 1.4 -->
<a href="{% url url_name %}">link which calls some_view</a>
<!-- django >= 1.5 or with {% load url from future %} in your template -->
<a href="{% url 'url_name' %}">link which calls some_view</a>
This will be rendered as:
<a href="...
Unique fields that allow nulls in Django
...pty string by providing your own customized model form for Foo with a clean_bar method that turns the empty string into None:
class FooForm(forms.ModelForm):
class Meta:
model = Foo
def clean_bar(self):
return self.cleaned_data['bar'] or None
class FooAdmin(admin.ModelAdmin...