大约有 47,000 项符合查询结果（耗时：0.0780秒） [XML]
Signed to unsigned conversion in C - is it always safe?
...unsigned values, resulting in a large result (depending on the values of u and i).
Long Answer
According to the C99 Standard:
6.3.1.8 Usual arithmetic conversions
If both operands have the same type, then no further conversion is needed.
Otherwise, if both operands have signed intege...
Uninstall / remove a Homebrew package including all its dependencies
...
EDIT:
It looks like the issue is now solved using an external command called brew rmdeps or brew rmtree.
To install and use, issue the following commands:
$ brew tap beeftornado/rmtree
$ brew rmtree <package>
See the above link for more information and discussion.
Original answ...
Facebook database design?
...
Keep a friend table that holds the UserID and then the UserID of the friend (we will call it FriendID). Both columns would be foreign keys back to the Users table.
Somewhat useful example:
Table Name: User
Columns:
UserID PK
EmailAddress
Password
Ge...
Linear Regression and group by in R
...ction. My data is an annual time series with one field for year (22 years) and another for state (50 states). I want to fit a regression for each state so that at the end I have a vector of lm responses. I can imagine doing for loop for each state then doing the regression inside the loop and adding...
In Clojure, when should I use a vector over a list, and the other way around?
...
Once again, it seems I've answered my own question by getting impatient and asking it in #clojure on Freenode. Good thing answering your own questions is encouraged on Stackoverflow.com :D
I had a quick discussion with Rich Hickey, and here is the gist of it.
[12:21] <Raynes> Vectors a...
Use RSA private key to generate public key?
I don't really understand this one:
9 Answers
9
...
Waiting until two async blocks are executed before starting another block
When using GCD, we want to wait until two async blocks are executed and done before moving on to the next steps of execution. What is the best way to do that?
...
Xcode 6 beta 2 issue exporting .ipa: “Your account already has a valid iOS distribution certificate”
...
This is what worked for me.
On my machine I kept both Xcode 5 and Xcode 6 beta.
From Xcode 6 beta, Archive the project. Close Xcode 6.
Open Xcode 5, go to Organizer and export as Ad Hoc build with proper provisioning profile.
That's it!
...
Understanding “randomness”
I can't get my head around this, which is more random?
28 Answers
28
...
How does Duff's device work?
I've read the article on Wikipedia on the Duff's device , and I don't get it. I am really interested, but I've read the explanation there a couple of times and I still don't get it how the Duff's device works.
...