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How to catch integer(0)?
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If it's specifically zero length integers, then you want something like
is.integer0 <- function(x)
{
is.integer(x) && length(x) == 0L
}
Check it with:
is.integer0(integer(0)) #TRUE
is.integer0(0L) #FALSE
is.integer0(...
Using LINQ to remove elements from a List
...the authors from the previous collection. Alternatively, you can use RemoveAll:
authorsList.RemoveAll(x => x.FirstName == "Bob");
If you really need to do it based on another collection, I'd use a HashSet, RemoveAll and Contains:
var setToRemove = new HashSet<Author>(authors);
authorsLi...
How to get a pixel's x,y coordinate color from an image?
...http://jsfiddle.net/thirtydot/9SEMf/869/ I used jQuery for convenience in all of this, but it is by no means required.
Note: getImageData falls under the browser's same-origin policy to prevent data leaks, meaning this technique will fail if you dirty the canvas with an image from another domain o...
Kill child process when parent process is killed
...plication dies, you are still left with child processes running. What we really want is for the child processes to die as soon as the main process dies.
The solution is to use "job objects" http://msdn.microsoft.com/en-us/library/ms682409(VS.85).aspx.
The idea is to create a "job object" for your ...
How can I access “static” class variables within class methods in Python?
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As with all good examples, you've simplified what you're actually trying to do. This is good, but it is worth noting that python has a lot of flexibility when it comes to class versus instance variables. The same can be said of meth...
Why does Java's hashCode() in String use 31 as a multiplier?
... i == (i << 5) - i. Modern VMs do this sort of optimization automatically.
(from Chapter 3, Item 9: Always override hashcode when you override equals, page 48)
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REST API Best practices: Where to put parameters? [closed]
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The official rule URIs and the draft sepc were really useful & interesting! :-)
– KajMagnus
Apr 16 '11 at 10:54
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Converting strings to floats in a DataFrame
...newer version of pandas (0.17 and up), you can use to_numeric function. It allows you to convert the whole dataframe or just individual columns. It also gives you an ability to select how to treat stuff that can't be converted to numeric values:
import pandas as pd
s = pd.Series(['1.0', '2', -3])
p...
How exactly does tail recursion work?
...nt one but without explicit recursion (that is, without explicit function calls). If you change the logic into something non-equivalent, you may indeed make the function loop forever in some or all cases.
– Alexey Frunze
Mar 20 '13 at 9:30
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multiple packages in context:component-scan, spring config
...lsorily need to add specific packages or it can scan sub packages automatically if we only define the top level package?
– Nikhil Sahu
Jun 17 '16 at 13:52
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