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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...
“open/close” SqlConnection or keep open?
...th static methods. Each of these methods opens/closes SQL connection when called:
6 Answers
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What's the fastest way to merge/join data.frames in R?
...(y) from main.d group by g1, g2"))
)
The outputs from the two benchmark call comparing the merge calculations are:
Joining by: x
test replications elapsed relative user.self sys.self user.child sys.child
3 data.table 1 0.34 1.000000 0.31 0.01 NA NA
2 ...
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.
...
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...
Can a decorator of an instance method access the class?
I have something roughly like the following. Basically I need to access the class of an instance method from a decorator used upon the instance method in its definition.
...
How to serve an image using nodejs
...
2016 Update
Examples with Express and without Express that actually work
This question is over 5 years old but every answer has some problems.
TL;DR
Scroll down for examples to serve an image with:
express.static
express
connect
http
net
All of the examples are also on GitHub: htt...
Proper way to declare custom exceptions in modern Python?
...tionError(Exception):
def __init__(self, message, errors):
# Call the base class constructor with the parameters it needs
super(ValidationError, self).__init__(message)
# Now for your custom code...
self.errors = errors
That way you could pass dict of error me...