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How does python numpy.where() work?
...
How do they achieve internally that you are able to pass something like x > 5 into a method?
The short answer is that they don't.
Any sort of logical operation on a numpy array returns a boolean array. (i.e. __gt__, __lt__, etc all return boolea...
Why use Abstract Base Classes in Python?
...emented classes.
Long version
There is a contract between a class and its callers. The class promises to do certain things and have certain properties.
There are different levels to the contract.
At a very low level, the contract might include the name of a method or its number of parameters.
In a s...
Validation failed for one or more entities while saving changes to SQL Server Database using Entity
...trings.
var errorMessages = ex.EntityValidationErrors
.SelectMany(x => x.ValidationErrors)
.Select(x => x.ErrorMessage);
// Join the list to a single string.
var fullErrorMessage = string.Join("; ", errorMessages);
// Combine the origin...
sqlite database default time value 'now'
...ime('%s','now'))
);
insert into example(data) values
('foo')
,('bar')
;
select
id
,data
,created_at as epoch
,datetime(created_at, 'unixepoch') as utc
,datetime(created_at, 'unixepoch', 'localtime') as localtime
from example
order by id
;
id|data|epoch |utc |localtime
1 |foo ...
How to add a custom loglevel to Python's logging facility
...for my application, as I don't think that debug() is sufficient. Additionally log(5, msg) isn't what I want. How can I add a custom loglevel to a Python logger?
...
How to programmatically send SMS on the iPhone?
...t with predefined (prefill) body text. Thos body text should be the manual selection from 4 possible options. E.g. The app opens and pop-ups "select reason". Then 4 options are available. Next the user selects one of these 4 options and then an automatic SMS is sent having as body text the choice of...
How to convert timestamp to datetime in MySQL?
...
SELECT from_unixtime( TIMESTAMP( "2011-12-01", "22:01:23.048" ) ) doesn't work. why? using v5.6
– Janus Troelsen
Feb 4 '14 at 18:44
...
C# switch statement limitations - why?
...values of switch labels are distinct (so that only one switch block can be selected for a given switch-expression)
Consider this code example in the hypothetical case that non-constant case values were allowed:
void DoIt()
{
String foo = "bar";
Switch(foo, foo);
}
void Switch(String val1...
A python class that acts like dict
...er) instead of simply delegating to the instance's __dict__ - which essentially means you're creating two dicts for every instance.
– Aaron Hall♦
Jan 8 '17 at 0:39
8
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Why does this loop produce “warning: iteration 3u invokes undefined behavior” and output more than 4
...
If during the evaluation of an expression, the result is not mathematically defined or not in the range of
representable values for its type, the behavior is undefined. [ Note: most existing implementations of C++
ignore integer overflows. Treatment of division by zero, forming a remainde...