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How to combine multiple conditions to subset a data-frame using “OR”?
...< 4) , ]
Some people criticize the use of which as not needed, but it does prevent the NA values from throwing back unwanted results. The equivalent (.i.e not returning NA-rows for any NA's in V1 or V2) to the two options demonstrated above without the which would be:
new.data <- data[ !is...
SQL Call Stored Procedure for each Row without using a cursor
...sometimes at the expense of changing the schema).
However, this snippet does have its place..
-- Declare & init (2008 syntax)
DECLARE @CustomerID INT = 0
-- Iterate over all customers
WHILE (1 = 1)
BEGIN
-- Get next customerId
SELECT TOP 1 @CustomerID = CustomerID
FROM Sales.Custo...
Calling virtual functions inside constructors
...structed from the base up, “base before derived”.
[...]
Destruction is done “derived class before base class”, so virtual functions behave as in constructors: Only the local definitions are used – and no calls are made to overriding functions to avoid touching the (now destroyed) derived c...
Pipe subprocess standard output to a variable [duplicate]
...sing the subprocess module, and store the output in a variable. However, I do not want the command's output to be printed to the terminal.
For this code:
...
Why am I getting this error: No mapping specified for the following EntitySet/AssociationSet - Entit
...
When you first create a model-first model, it's in a state that the SSDL does not exist. You can drag entities, associate them and so forth and yet, if you take a look at the SSDL on the EDMX file, you will see that none of the entities have an associated storage table in the SSDL.
That changes w...
What is the easiest way to remove the first character from a string?
...23,987,43"
I'm always looking for the fastest and most readable way of doing things:
require 'benchmark'
N = 1_000_000
puts RUBY_VERSION
STR = "[12,23,987,43"
Benchmark.bm(7) do |b|
b.report('[0]') { N.times { "[12,23,987,43"[0] = '' } }
b.report('sub') { N.times { "[12,23,987,43".sub(/...
Understanding the difference between Object.create() and new SomeFunction()
...ect, where as in the new Function() form the declared properties/functions do not form the prototype.
Yes, Object.create builds an object that inherits directly from the one passed as its first argument.
With constructor functions, the newly created object inherits from the constructor's prototyp...
Scala: What is a TypeTag and how do I use it?
...they somehow replaced Manifests. Information on the Internet is scarce and doesn't provide me with a good sense of the subject.
...
How to dynamically change a web page's title?
...at implements a set of tabs each showing different content. The tab clicks do not refresh the page but hide/unhide contents at the client side.
...
How to export revision history from mercurial or git to cvs?
...hile we want to commit our code and all of our revision history to cvs. We don't have write access to the project's cvs repo so we can't commit very frequently. What tool can we use to export our revision history to cvs? Currently we were thinking of using git or mercurial but we could use another d...