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notifyDataSetChanged example
I'm trying to use in my Android Application the notifyDataSetChanged() method for an ArrayAdapter but it doesn't work for me.
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Installing older version of R package
I am trying to use Rpy2 and ggplot2 but I get an error. After some searching for the error online, I found that the error occurs because there are changes in the ggplot2 package that are not yet reflected in Rpy2 (for example, see this post (Edit: Link is now dead)).
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Why does Python pep-8 strongly recommend spaces over tabs for indentation?
I see on Stack Overflow and PEP 8 that the recommendation is to use spaces only for indentation in Python programs. I can understand the need for consistent indentation and I have felt that pain.
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Attempt to present UIViewController on UIViewController whose view is not in the window hierarchy
Just started using Xcode 4.5 and I got this error in the console:
33 Answers
33
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How to loop through file names returned by find?
...st). If you have time, read through the rest to see several different ways and the problems with most of them.
The full answer:
The best way depends on what you want to do, but here are a few options. As long as no file or folder in the subtree has whitespace in its name, you can just loop over ...
Automatically plot different colored lines
I'm trying to plot several kernel density estimations on the same graph, and I want them to all be different colors. I have a kludged solution using a string 'rgbcmyk' and stepping through it for each separate plot, but I start having duplicates after 7 iterations. Is there an easier/more efficien...
How to extract the decision rules from scikit-learn decision-tree?
...e output for a tree that is trying to return its input, a number between 0 and 10.
def tree(f0):
if f0 <= 6.0:
if f0 <= 1.5:
return [[ 0.]]
else: # if f0 > 1.5
if f0 <= 4.5:
if f0 <= 3.5:
return [[ 3.]]
else: # if f0 > 3.5
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Overriding superclass property with different type in Swift
...properties. Instead you can create an extra variable in the subclass that handles the new class type:
class Chassis {}
class RacingChassis : Chassis {}
class Car {
var chassis = Chassis()
}
class RaceCar: Car {
var racingChassis = RacingChassis()
override var chassis: Chassis {
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Condition within JOIN or WHERE
...al algebra allows interchangeability of the predicates in the WHERE clause and the INNER JOIN, so even INNER JOIN queries with WHERE clauses can have the predicates rearrranged by the optimizer so that they may already be excluded during the JOIN process.
I recommend you write the queries in the mo...
What does it mean when git says a file “needs update”?
...laining this marked as a TODO. If someone could explain A) what it means; and B) how to fix it, I would be extremely grateful.
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