大约有 40,000 项符合查询结果（耗时：0.0593秒） [XML]
What is “:-!!” in C code?
...sizeof(struct { int: -!!(e); }))
(e): Compute expression e.
!!(e): Logically negate twice: 0 if e == 0; otherwise 1.
-!!(e): Numerically negate the expression from step 2: 0 if it was 0; otherwise -1.
struct{int: -!!(0);} --> struct{int: 0;}: If it was zero, then we declare a struct with an an...
Is there a range class in C++11 for use with range based for loops?
...:irange, which is a bit more focused in scope.
C++20's range library will allow you to do this via view::iota(start, end).
share
|
improve this answer
|
follow
...
Efficiently updating database using SQLAlchemy ORM
...ngs in mind when using the ORM and plain SQL in the same transaction. Basically, from one side, ORM data modifications will only hit the database when you flush the changes from your session. From the other side, SQL data manipulation statements don't affect the objects that are in your session.
So...
Pass a parameter to a fixture function
... through the tester fixture.
I had a similar problem--I have a fixture called test_package, and I later wanted to be able to pass an optional argument to that fixture when running it in specific tests. For example:
@pytest.fixture()
def test_package(request, version='1.0'):
...
request....
Creating JS object with Object.create(null)?
...t.create(null) doesn't inherit from anything and thus has no properties at all.
In other words: A javascript object inherits from Object by default, unless you explicitly create it with null as its prototype, like: Object.create(null).
{} would instead be equivalent to Object.create(Object.prototy...
Return a value if no rows are found in Microsoft tSQL
... S.Id = @SiteId and S.Status = 1 AND
(S.WebUserId = @WebUserId OR S.AllowUploads = 1)
share
|
improve this answer
|
follow
|
...
Is it possible to specify your own distance function using scikit-learn K-Means Clustering?
...
Here's a small kmeans that uses any of the 20-odd distances in
scipy.spatial.distance, or a user function.
Comments would be welcome (this has had only one user so far, not enough);
in particular, what are your N, dim, k, metric ?
#!/u...
What are the best JVM settings for Eclipse? [closed]
...jvm.dll
-vmargs
-Dosgi.requiredJavaVersion=1.6
-Declipse.p2.unsignedPolicy=allow
-Xms128m
-Xmx384m
-Xss4m
-XX:PermSize=128m
-XX:MaxPermSize=384m
-XX:CompileThreshold=5
-XX:MaxGCPauseMillis=10
-XX:MaxHeapFreeRatio=70
-XX:+CMSIncrementalPacing
-XX:+UnlockExperimentalVMOptions
-XX:+UseG1GC
-XX:+UseFast...
How to do what head, tail, more, less, sed do in Powershell? [closed]
...an above option
gc log.txt | more # or less if you have it installed
gc log.txt | %{ $_ -replace '\d+', '($0)' } # sed
This works well enough for small files, larger ones (more than a few MiB) are probably a bit slow.
The PowerShell Community Extensions include some cmdlets fo...
namedtuple and default values for optional keyword arguments
...lds)
>>> Node()
Node(val=None, left=None, right=None)
Order
In all versions of Python, if you set fewer default values than exist in the namedtuple, the defaults are applied to the rightmost parameters. This allows you to keep some arguments as required arguments.
>>> Node.__ne...