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explicit casting from super class to subclass
...
In order to avoid this kind of ClassCastException, if you have:
class A
class B extends A
You can define a constructor in B that takes an object of A. This way we can do the "cast" e.g.:
public B(A a) {
super(a.arg1, a.a...
Array extension to remove object by value
... but I would rename its declaration slightly to remove(object: Element) in order to comply with the Swift API design guidelines and avoid verbosity. I have submitted an edit reflecting this.
– swiftcode
Oct 12 '16 at 16:07
...
What is the Swift equivalent of isEqualToString in Objective-C?
...e considered equal if they contain exactly the same characters in the same order:
let quotation = "We're a lot alike, you and I."
let sameQuotation = "We're a lot alike, you and I."
if quotation == sameQuotation {
println("These two strings are considered equal")
}
// prints "These two strings ...
NumPy or Pandas: Keeping array type as integer while having a NaN value
...that has NA converting to the new 'Int64' dtype will give you an error. In order to solve this you have to round the numbers and then do ".astype('Int64')"
s1 = pd.Series([1.434, 2.343, np.nan])
#without round() the next line returns an error
s1.astype('Int64')
#cannot safely cast non-equivalent f...
C++ new int[0] — will it allocate memory?
...w[i] you need a bit more memory than that which you are trying to alloc in order to store the size of the array (which is later used by delete[] when deallocating)
– pqnet
Oct 20 '17 at 15:51
...
Two color borders
Client wants two color borders for an embossed look. Can I do this on one element? I was hoping to avoid stacking two DOM elements with individual borders.
...
Ways to implement data versioning in MongoDB
..., content: "bar" }
]
}
data contains all versions. The data array is ordered, new versions will only get $pushed to the end of the array. data.vid is the version id, which is an incrementing number.
Get the most recent version:
find(
{ "_id":ObjectId("...") },
{ "data":{ $slice:-1 } ...
What is the difference between a generative and a discriminative algorithm?
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A generative algorithm models how the data was generated in order to categorize a signal. It asks the question: based on my generation assumptions, which category is most likely to generate this signal?
A discriminative algorithm does not care about how the data was generated, it si...
Razor view engine, how to enter preprocessor(#if debug)
...ompiled so #IF DEBUG can't work in a view. If you want to compile view in order to access IF DEBUG config, you need to :
Right click on your project in Visual Studio
Unload project
Edit project
change the following attribute from false to true
<MvcBuildViews>true</MvcBuildViews>
...
How can I remove the first line of a text file using bash/sed script?
...istopherSahnwaldt -- tail is much, much slower than the sed variant, by an order of magnitude. I'm testing it on a file of 500,000K lines (no more than 50 chars per line). However, I then realized I was using the FreeBSD version of tail (which comes with OS X by default). When I switched to GNU tail...