大约有 45,000 项符合查询结果（耗时：0.0572秒） [XML]
How to find list intersection?
...
If order is not important and you don't need to worry about duplicates then you can use set intersection:
>>> a = [1,2,3,4,5]
>>> b = [1,3,5,6]
>>> list(set(a) & set(b))
[1, 3, 5]
...
How to avoid isset() and empty()
... mean you should.
These warnings are there to help you, not to annoy you. If you get a warning "You're trying to work with something that doesn't exist!", your reaction should be "Oops, my bad, let me fix that ASAP." How else are you going to tell the difference between "variables that work just fi...
How to find a text inside SQL Server procedures / triggers?
...t. But my suggestion is how to build technical wealth—spending more time now to be faster, more agile, and more reliable later. Read the article Big Ball of Mud for some ideas around this.
– ErikE
Sep 5 '16 at 16:41
...
How do I upgrade my ruby 1.9.2-p0 to the latest patch level using rvm?
...sk RVM to list the ruby versions available to install by running rvm list known.
In the output you should now see:
# MRI Rubies
...
[ruby-]1.9.2[-p320]
...
The square brackets around the patch level indicate that this is currently RVM's default patch level for ruby 1.9.2.
Finally, to install th...
https URL with token parameter : how secure is it?
...k, site discovers the cookie and can present the user with the old data.
Now, the user wants to use a different browser on a different machine. In this case, offer a "transfer" button. When the user clicks on this button, she will get a "token". She can use this token on another computer to reset ...
Detect iPad users using jQuery?
Is there a way to detect if the current user is using an iPad using jQuery/JavaScript?
4 Answers
...
Why does “_” (underscore) match “-” (hyphen)?
...).
(From section 3.3.4.7. Pattern Matching in the MySQL documentation.)
If you want to use the underscore in like as a literal, you have to escape it:
select * from a where name like '%taz\_manual%.pdf%';
share
...
Read file from line 2 or skip header row
...
if you need the header later, instead of next(f) use f.readline() and store it as a variable
– damned
Oct 8 '13 at 5:38
...
detach all packages while working in R
... value present. One can test for this with names(sessionInfo()$otherPkgs). If it returns NULL, then this is the cause.
– mmfrgmpds
Sep 20 '19 at 16:31
|
...
Is there a math nCr function in python? [duplicate]
I'm looking to see if built in with the math library in python is the nCr (n Choose r) function:
2 Answers
...