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Dynamically select data frame columns using $ and a character value
...3 = sample(5,10,repl=T) )
# We want to sort by 'col3' then by 'col1'
sort_list <- c("col3","col1")
# Use 'do.call' to call order. Seccond argument in do.call is a list of arguments
# to pass to the first argument, in this case 'order'.
# Since a data.frame is really a list, we just subset ...
How can I convert string date to NSDate?
... */
let date = dateFormatter.dateFromString(/* your_date_string */)
For further query, check NSDateFormatter and DateFormatter classes of Foundation framework for Objective-C and Swift, respectively.
Swift 3 and later (Swift 4 included)
let dateFormatter = DateFormatter()...
REST API Best practices: Where to put parameters? [closed]
...
The official rule URIs and the draft sepc were really useful & interesting! :-)
– KajMagnus
Apr 16 '11 at 10:54
...
How would you implement an LRU cache in Java?
...y at the back of the iteration order regardless of whether that entry initially exists in the cache)
– Pacerier
Feb 23 '12 at 18:26
...
Any reason why scala does not explicitly support dependent types?
...here are path dependent types and I think it is possible to express almost all the features of such languages as Epigram or Agda in Scala, but I'm wondering why Scala does not support this more explicitly like it does very nicely in other areas (say, DSLs) ?
Anything I'm missing like "it is not ne...
Setting Authorization Header of HttpClient
...ent = new HttpClient())
{
client.DefaultRequestHeaders.Authorization = _username.ToAuthHeaderValue(_password);
}
Again I think 2 above options make the client using statement a bit less repetitive. Keep in mind that it's best practice to reuse the HttpClient if you are making multiple http ca...
How to specify an area name in an action link?
... This is a very good tip! But it gives not expected results with MVC 2.. Small correction - Html.ActionLink("home", "Index", new { area = "", controller = "Home" })
– Alexander Beletsky
Nov 20 '10 at 10:36
...
Having Django serve downloadable files
..._str(file_name)
response['X-Sendfile'] = smart_str(path_to_file)
# It's usually a good idea to set the 'Content-Length' header too.
# You can also set any other required headers: Cache-Control, etc.
return response
Of course, this will only work if you have control over your server, or your hostin...
TCPClient TCP客户端扩展：连接TCP服务器进行文本消息通信 · App Inventor 2 中文网
...、ISO-8859-1、UTF-16BE、UTF-16LE、UTF-16。
字符集US-ASCII Charset_USASCII
US-ASCII 字符集常量。
字符集UTF-8 Charset_UTF8
UTF-8 字符集常量。
字符集ISO-Latin-1 Charset_ISO_Latin_1
ISO-8859-1 字符集常量。
字符集UTF-16BE Charset_UTF16BE
UTF-16BE 字符...
Is it possible to use Java 8 for Android development?
...
java 8
Android supports all Java 7 language features and a subset of Java 8 language features that vary by platform version.
To check which features of java 8 are supported
Use Java 8 language features
We've decided to add support for Java 8 ...