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How to convert List to int[] in Java? [duplicate]
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Unfortunately, I don't believe there really is a better way of doing this due to the nature of Java's handling of primitive types, boxing, arrays and generics. In particular:
List<T>.toArray won't work because there's no conversion from Integer to int
You ...
Implementing INotifyPropertyChanged - does a better way exist?
...er with C# 5:
protected bool SetField<T>(ref T field, T value,
[CallerMemberName] string propertyName = null)
{...}
which can be called like this:
set { SetField(ref name, value); }
with which the compiler will add the "Name" automatically.
C# 6.0 makes the implementation easier:
protec...
Convert Python dict into a dataframe
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The error here, is since calling the DataFrame constructor with scalar values (where it expects values to be a list/dict/... i.e. have multiple columns):
pd.DataFrame(d)
ValueError: If using all scalar values, you must must pass an index
You could ...
Compare two List objects for equality, ignoring order [duplicate]
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If you want them to be really equal (i.e. the same items and the same number of each item), I think that the simplest solution is to sort before comparing:
Enumerable.SequenceEqual(list1.OrderBy(t => t), list2.OrderBy(t => t))
Edit:
Here is...
ISO time (ISO 8601) in Python
...atetime.datetime.now().astimezone().isoformat()
>>> 2020-03-20T14:32:16.458361+13:00
Notice there is a bug when using astimezone() on utc time. This gives an incorrect result:
datetime.datetime.utcnow().astimezone().isoformat() #Incorrect result
For Python 2, see and use pytz.
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Numpy: Divide each row by a vector element
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Why would one omit the close tag?
...e file (and possibly some other factors I don't want to bore you with).
Finally, many PHP frameworks including Symfony, Zend and Laravel (there is no mention of this in the coding guidelines but it follows the suit) and the PSR-2 standard (item 2.2) require omission of the closing tag. PHP manual it...
Math - mapping numbers
...))
– Chris Chiasson
Mar 9 '17 at 18:32
To reverse the direction, the formula is ( (X-A)/(A-B) * (C-D) ) * -1 + D
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What is the advantage of GCC's __builtin_expect in if else statements?
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I guess it should be something like:
cmp $x, 0
jne _foo
_bar:
call bar
...
jmp after_if
_foo:
call foo
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after_if:
You can see that the instructions are arranged in such an order that the bar case precedes the foo case (as opposed to the C code). This can utilise the CPU ...
Many-to-many relationship with the same model in rails?
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For reference: the Rails documentation on the subject. There's a section called “Many-to-many”, and of course the documentation on the class methods themselves.
Simplest scenario, uni-directional, no additional fields
This is the most compact in code.
I'll start out with this basic schema fo...
