大约有 47,000 项符合查询结果（耗时：0.0302秒） [XML]
Which method performs better: .Any() vs .Count() > 0?
...le<T> sequence.
For just IEnumerable<T>, then Any() will generally be quicker, as it only has to look at one iteration. However, note that the LINQ-to-Objects implementation of Count() does check for ICollection<T> (using .Count as an optimisation) - so if your underlying data-sou...
Python unittest - opposite of assertRaises?
...the correct solution in fact. The solution proposed by user9876 is conceptually flawed: if you test for the non-raising of say ValueError, but ValueError is instead raised, your test must exit with a failure condition, not an error one. On the other hand, if in running the same code you would raise ...
Objective-C : BOOL vs bool
..., you can assume that BOOL is a char. You can use the (C99) bool type, but all of Apple's Objective-C frameworks and most Objective-C/Cocoa code uses BOOL, so you'll save yourself headache if the typedef ever changes by just using BOOL.
...
Best way to do multiple constructors in PHP
...
<?php
class Student
{
public function __construct() {
// allocate your stuff
}
public static function withID( $id ) {
$instance = new self();
$instance->loadByID( $id );
return $instance;
}
public static function withRow( array $row ) {
...
How to assert output with nosetest/unittest in python?
...rarily replacing sys.stdout. I prefer the context manager because it wraps all the bookkeeping into a single function, so I don't have to re-write any try-finally code, and I don't have to write setup and teardown functions just for this.
import sys
from contextlib import contextmanager
from String...
How can I rename a field for all documents in MongoDB?
...above are: { upsert:false, multi:true }. You need the multi:true to update all your records.
Or you can use the former way:
remap = function (x) {
if (x.additional){
db.foo.update({_id:x._id}, {$set:{"name.last":x.name.additional}, $unset:{"name.additional":1}});
}
}
db.foo.find().forEach...
Use numpy array in shared memory for multiprocessing
...
To add to @unutbu's (not available anymore) and @Henry Gomersall's answers. You could use shared_arr.get_lock() to synchronize access when needed:
shared_arr = mp.Array(ctypes.c_double, N)
# ...
def f(i): # could be anything numpy accepts as an index such another numpy array
with ...
Python error “ImportError: No module named”
Python is installed in a local directory.
28 Answers
28
...
lodash multi-column sortBy descending
...dash.com/docs#orderBy) in Lodash as of 4.3.0. The normal sort function is called _.sortBy(lodash.com/docs#sortBy)
– Nidhin David
Feb 12 '16 at 11:19
2
...
Python - Create a list with initial capacity
...bject %d" % ( i, )
result.append(message)
return result
def doAllocate( size=10000 ):
result=size*[None]
for i in range(size):
message= "some unique object %d" % ( i, )
result[i]= message
return result
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