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How can I make the computer beep in C#?
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I just tested in Win 7 x64 RC, and although the internal speaker didn't beep, there was a beep through speakers when I had them plugged in and on. I guess it's just the internal (mobo) speaker that won't beep. Thanks for the info @Lck.
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R memory management / cannot allocate vector of size n Mb
...eate the object you need in one session.
If the above cannot help, get a 64-bit machine with as much RAM as you can afford, and install 64-bit R.
If you cannot do that there are many online services for remote computing.
If you cannot do that the memory-mapping tools like package ff (or bigmem...
“/usr/bin/ld: cannot find -lz”
...lib1g-dev did not fix it. Installing lib32z1-dev got me past it. I have a 64 bit system and it seems like it wanted the 32 bit library.
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iOS开发过程中的各种tips - 更多技术 - 清泛网 - 专注C/C++及内核技术
...直接在介绍AFNetworking的时候详解吧。
25.使用NSURLConnection下载数据
1. 创建对象
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:[NSURL URLWithString:@"http://www.baidu.com"]];
[NSURLConnection connectionWithRequest:request delegate:self];
2. NSURLCon...
Difference between map, applymap and apply methods in Pandas
... b d e
Utah -0.029638 1.081563 1.280300
Ohio 0.647747 0.831136 -1.549481
Texas 0.513416 -0.884417 0.195343
Oregon -0.485454 -0.477388 -0.309548
In [118]: f = lambda x: x.max() - x.min()
In [119]: frame.apply(f)
Out[119]:
b 1.133201
d 1.965980
e 2.829781
dt...
What's with 181783497276652981 and 8682522807148012 in Random (Java 7)?
...ses a multiplicative linear congruential generator (MLCG) with c=0 and m=2^64. (The modulus 2^64 is implicitly given by the overflow of 64bit long integers)
Because of the zero c and the power-of-2-modulus, the "quality" (cycle length, bit-correlation, ...) is limited. As the paper says, besides the...
How to validate an e-mail address in swift?
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let emailRegEx = "[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,64}"
let emailPred = NSPredicate(format:"SELF MATCHES %@", emailRegEx)
return emailPred.evaluate(with: email)
}
for versions of Swift earlier than 3.0:
func isValidEmail(email: String) -> Bool {
let emailRe...
How to convert an IPv4 address into a integer in C#?
...ses. Meanwhile, the IPAddress.Address property, while deprecated, is an Int64 that returns the unsigned 32-bit value of the IPv4 address (the catch is, it's in network byte order, so you need to swap it around).
For example, my local google.com is at 64.233.187.99. That's equivalent to:
64*2^24 + ...
Maximum length for MySQL type text
... (255 Bytes)
BLOB, TEXT L + 2 bytes, where L < 2^16 (64 Kilobytes)
MEDIUMBLOB, MEDIUMTEXT L + 3 bytes, where L < 2^24 (16 Megabytes)
LONGBLOB, LONGTEXT L + 4 bytes, where L < 2^32 (4 Gigabytes)
L is the number of bytes in your text field. So the maximum numb...
What is causing “Unable to allocate memory for pool” in PHP?
...allowing only 32MB is ridiculously low. PHP was designed when servers were 64MB and most scripts were using one php file per page. Nowadays solutions like Magento require more than 10k files (~60Mb in APC). You should allow enough memory so most of php files are always cached. It's not a waste, it's...