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Reading CSV files using C#
...sualBasic but it works in C# just as well - remember that at the end it is all just IL)
use the Microsoft.VisualBasic.FileIO.TextFieldParser class to parse CSV file
Here is the sample code:
using (TextFieldParser parser = new TextFieldParser(@"c:\temp\test.csv"))
{
parser.TextFieldType = Fiel...
Convert column classes in data.table
...hat is the idiomatic way of doing this for a subset of columns (instead of all of them)? I've defined a character vector convcols of columns. dt[,lapply(.SD,as.numeric),.SDcols=convcols] is almost instant while dt[,convcols:=lapply(.SD,as.numeric),.SDcols=convcols] almost freezes up R, so I'm guessi...
:not(:empty) CSS selector is not working?
...idered empty by the HTML definition of "empty", since the content model of all void elements is always empty. So they will always match the :empty pseudo-class, whether or not they have a value. This is also why their value is represented by an attribute in the start tag, rather than text content wi...
What's the difference between Perl's backticks, system, and exec?
...It never returns true, because if the command is found it never returns at all.
There is also no point in returning STDOUT, STDERR or exit status of the command.
You can find documentation about it in perlfunc,
because it is a function.
system
executes a command and your Perl script is con...
knitr Markdown highlighting in Emacs?
...r the former you need polymode and for the latter markdown.el. Besides, if all you want is to just switch the ESS engine from Sweave to knitr (without highlighting!), there is no need to go through all the complication of this article, just add (setq ess-swv-processor 'knitr) in you init file.
...
Connect to Amazon EC2 file directory using Filezilla and SFTP
...tering a password to proceed past the dialog.
Note: FileZilla automatically figures out which key to use. You do not need to specify the key after importing it as described above.
If you use Cyberduck follow this.
Check this post if you have any permission issues.
...
Is file append atomic in UNIX?
...ger (linux seems to have it set to 4096).
This assume that you're talking all fully POSIX-compliant components. For instance, this isn't true on NFS.
But assuming you write to a log file you opened in 'O_APPEND' mode and keep your lines (including newline) under 'PIPE_BUF' bytes long, you should ...
Xcode 6 Storyboard the wrong size?
...you to get used to size classes as they are the future, and you will eventually jump in anyway at some point."
You probably haven't added the layout constraints.
Select your label, tap the layout constraints button on the bottom:
On that menu add width and height (it should NOT be the same as...
How can I let a table's body scroll but keep its head fixed in place?
...in a set size. I need the headers at the top of the table to stay there at all times but I also need the body of the table to scroll no matter how many rows are added to the table. Think a mini version of excel. This seems like a simple task but almost every solution I have found on the web has some...
What is a serialVersionUID and why should I use it?
...ization runtime associates with each serializable class a version number, called a serialVersionUID, which is used during deserialization to verify that the sender and receiver of a serialized object have loaded classes for that object that are compatible with respect to serialization. If the receiv...