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NumPy or Pandas: Keeping array type as integer while having a NaN value
...s best to work with float series where possible, even when the series is upcast from int to float due to inclusion of NaN values. This enables vectorised NumPy-based calculations where, otherwise, Python-level loops would be processed.
The docs do suggest : "One possibility is to use dtype=object a...
Difference between List, List, List, List, and List
... you pointed out this is not the case. The reason why was that if we could cast from List<String> to List<Object>, then we could put Objects into that list, thus violating the original contract of List<String> when attempting to retrieve an element.
– Peter
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Best practices to handle routes for STI subclasses in rails
...subclassing (unlike Rails 4) and works in Rails 3.
# initializers/acts_as_castable.rb
module ActsAsCastable
extend ActiveSupport::Concern
module ClassMethods
def new_with_cast(*args, &block)
if (attrs = args.first).is_a?(Hash)
if klass = descendant_class_from_attrs(attrs...
How to randomly select rows in SQL?
...rformance, this could be a better answer:
SELECT * FROM Table1
WHERE (ABS(CAST(
(BINARY_CHECKSUM
(keycol1, NEWID())) as int))
% 100) < 10
https://msdn.microsoft.com/en-us/library/cc441928.aspx
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How does Python manage int and long?
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Comment by Ted : As mentioned below beware that casting something to int that is larger than maxint will still result in a long >>>type(int(sys.maxint+1)) <type 'long'>
– StuartLC
Oct 25 '12 at 9:51
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How do you bind an Enum to a DropDownList control in ASP.NET?
...l.DropDownListFor(o => o.EnumProperty, Enum.GetValues(typeof(enumtype)).Cast<enumtype>().Select(x => new SelectListItem { Text = x.ToString(), Value = ((int)x).ToString() }))
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C read file line by line
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Why the cast (FILE*) fp ? Isn't fp is already a FILE * and also fopen() returns a FILE * ?
– Accountant م
Apr 4 '19 at 23:25
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How to generate a random number in C++?
...is intuition it is
only natural to search the web for some magic spells to cast to get
such random number in any possible context.
^^^ THAT kind of intuitive expectations IS VERY WRONG and harmful in all cases involving Pseudo-Random Number Generators - despite being reasonable for true random numb...
Should I store entire objects, or pointers to objects in containers?
...class pointers, and to handle all the collateral damage in object storage, casting, and so on. It took me a couple of months to convince myself that the new code was working. Incidentally, this made me think hard about how well-designed C++'s object model is.
On my current big project, my central d...
Android OnClickListener - identify a button
...s not correct. View is not a Button, but Button is a View. Though, you can cast a View to a Button. Keep in mind that the second way to do it is not recommended... maybe that v may not be a Button, which will generate a cast exception.
– Cristian
Jul 23 '10 at ...