大约有 48,000 项符合查询结果（耗时：0.0546秒） [XML]
How to find all occurrences of an element in a list?
...onverting outweighs the speed gain (tested on integer lists with 100, 1000 and 10000 elements).
NOTE: A note of caution based on Chris_Rands' comment: this solution is faster than the list comprehension if the results are sufficiently sparse, but if the list has many instances of the element that i...
How can I list (ls) the 5 last modified files in a directory?
...ed files:
ls -1t | head -5
The -1 (that's a one) says one file per line and the head says take the first 5 entries.
If you want the last 5 try
ls -1t | tail -5
share
|
improve this answer
...
rreplace - How to replace the last occurrence of an expression in a string?
...500 characters), your solution was three times faster than Alex's solution and four times faster than Mark's solution. Thanks to all for your answers!
– Barthelemy
Mar 31 '10 at 20:44
...
R object identification
... often ending up with a function producing output for which I don't understand the output data type. I'm expecting a list and it ends up being a list of lists or a data frame or something else. What's a good method or workflow for figuring out the output data type when first using a function?
...
Is there a way to cause git-reflog to show a date alongside each entry?
The git-reflog command doesn't by default show a date alongside each entry, which strikes me as a strange oversight; I think this would be very helpful.
...
Is there a way to instantiate objects from a string holding their class name?
...<DerivedA>;
map["DerivedB"] = &createInstance<DerivedB>;
And then you can do
return map[some_string]();
Getting a new instance. Another idea is to have the types register themself:
// in base.hpp:
template<typename T> Base * createT() { return new T; }
struct BaseFactor...
How to write an XPath query to match two attributes?
...
//div[@id='..' and @class='...]
should do the trick. That's selecting the div operators that have both attributes of the required value.
It's worth using one of the online XPath testbeds to try stuff out.
...
MySQL show current connection info
...ER();
This will return something like root@localhost so you get the host and the user.
To get the current database run this statement:
SELECT DATABASE();
Other useful functions can be found here: http://dev.mysql.com/doc/refman/5.0/en/information-functions.html
...
Get Selected index of UITableView
...is useful for me to have access to long pathRow = [selectedIndexPath row]; and long pathSection = [selectedIndexPath section]; when you need specific selections (note that NSInteger is a typedef long which coming from a C background makes more sense since both need %ld anyway.
–...
Multiple working directories with Git?
...t for contrib/workdir/git-new-workdir that does not rely on symbolic links and make sharing of objects and refs safer by making the borrowee and borrowers aware of each other.
See commit 799767cc9 (Git 2.5rc2)
That means you now can do a git worktree add <path> [<branch>]
Create <pa...