大约有 37,000 项符合查询结果（耗时：0.0458秒） [XML]
Unique combination of all elements from two (or more) vectors
...aybe what you are after
> expand.grid(a,b)
Var1 Var2
1 ABC 2012-05-01
2 DEF 2012-05-01
3 GHI 2012-05-01
4 ABC 2012-05-02
5 DEF 2012-05-02
6 GHI 2012-05-02
7 ABC 2012-05-03
8 DEF 2012-05-03
9 GHI 2012-05-03
10 ABC 2012-05-04
11 DEF 2012-05-04
12 GHI 2012-05-04
13 AB...
Why use try {} finally {} with an empty try block?
...
From http://blog.somecreativity.com/2008/04/10/the-empty-try-block-mystery/:
This methodology guards against a
Thread.Abort call interrupting the
processing. The MSDN page of
Thread.Abort says that “Unexecuted
finally blocks are executed before the...
How can I catch a “catchable fatal error” on PHP type hinting?
...d' catchable fatal error\n";
throw new ErrorException($errstr, $errno, 0, $errfile, $errline);
// return true;
}
return false;
}
set_error_handler('myErrorHandler');
class ClassA {
public function method_a (ClassB $b) {}
}
class ClassWrong{}
try{
$a = new ClassA;
$a->method_a...
How to show what a commit did?
...
509
git show <commit-id>
Documentation for git show
...
Best practices around generating OAuth tokens?
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answered Oct 26 '09 at 19:45
ZZ CoderZZ Coder
68.8k2828 gold badges126126 silver badges159159 bronze badges
...
How to trigger jQuery change event in code
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answered Nov 22 '10 at 15:51
John HartsockJohn Hartsock
75.3k2121 gold badges120120 silver badges142142 bronze badges
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Deleting array elements in JavaScript - delete vs splice
... myArray = ['a', 'b', 'c', 'd']
["a", "b", "c", "d"]
> delete myArray[0]
true
> myArray[0]
undefined
Note that it is not in fact set to the value undefined, rather the property is removed from the array, making it appear undefined. The Chrome dev tools make this distinction clear by pr...
Set the selected index of a Dropdown using jQuery
...uery
// sets selected index of a select box to the option with the value "0"
$("select#elem").val('0');
// sets selected index of a select box to the option with the value ""
$("select#elem").val('');
// sets selected index to first item using the DOM
$("select#elem")[0].selectedIndex = 0;
// ...
Counting array elements in Python [duplicate]
...
304
The method len() returns the number of elements in the list.
Syntax:
len(myArray)
Eg:
myAr...
Update an outdated branch against master in a Git repo
... |
edited Mar 2 '12 at 5:04
random
9,06877 gold badges6262 silver badges7676 bronze badges
answered Jan...