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Code-first vs Model/Database-first [closed]
...mitations you face when using code-first, e.g. you can not create a unique index on a field or you can not delete hierarchical data in a tree table for this you need a CTE using the context.Table.SqlQuery("select..."). Model/Database first do not have these drawbacks.
– Elisabe...
Difference between array_map, array_walk and array_filter
...values-directly, unless passed value by reference (array walk might remove indexes/elements as array_filter indirectly via anonymous function use clause passing the original array but it's a workaround). To conclude thus, changing values, nor if a value is returned or passed by reference is of less ...
Choice between vector::resize() and vector::reserve()
...ave an upper bound. Of course when in doubt, with vectors you can just use indexes instead of iterators, the difference is usually negligible.
– Steve Jessop
Sep 13 '11 at 9:33
4
...
Learn C first before learning Objective-C [closed]
...rrays with memcopy instead of taking data from one array to the other one, index for index. The result: A speed up by the factor 4. The graph animated smoothly, even on older PPC systems.
The weakness of C is that every more complex program gets ugly in the long run. Keeping C applications readable...
Is it possible to specify your own distance function using scikit-learn K-Means Clustering?
... in km:
clustercentre = centres[jcentre]
J indexes e.g. X[J], classes[J]
"""
def __init__( self, X, k=0, centres=None, nsample=0, **kwargs ):
self.X = X
if centres is None:
self.centres, self.Xtocentre, self.distances = kmeanssample...
Improving bulk insert performance in Entity framework [duplicate]
...it in all scenarios since it depends on multiple factors such as row size, index, trigger, etc.
It's normally recommended to be around 4000.
Also is there a way to tie it all in one transaction and not worry about it timing out
You can use Entity Framework transaction. Our library uses the tr...
How to write the Fibonacci Sequence?
... + b # a will now be 1, and b will also be 1, (0 + 1)
and usage:
for index, fibonacci_number in zip(range(10), fib()):
print('{i:3}: {f:3}'.format(i=index, f=fibonacci_number))
prints:
0: 0
1: 1
2: 1
3: 2
4: 3
5: 5
6: 8
7: 13
8: 21
9: 34
10: 55
...
Mimicking sets in JavaScript?
...
@mkirk - yes the item you are indexing in the set must have a string representation that can be the index key (e.g. it either is a string or has a toString() method that uniquely describes the item).
– jfriend00
Nov ...
Learning Python from Ruby; Differences and Similarities
...object collections together and b) when you need to iterate using multiple indexes. For example, to find all the palindromes in a string (assuming you have a function p() that returns true for palindromes), all you need is a single list comprehension:
s = 'string-with-palindromes-like-abbalabba'
l ...
What is Autoloading; How do you use spl_autoload, __autoload and spl_autoload_register?
...oad() function.
To demonstrate this behaviour, just create a file called index.php :
<?php
spl_autoload_register();
var_dump(new Main\Application);
Then create a folder named Main located right next to the index.php file. Finally, creates a file called Application.php located into Main and p...