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Fastest way to replace NAs in a large data.table
...= function(dt) remove_na(dt)
f_gdata = function(dt, un = 0) gdata::NAToUnknown(dt, un)
f_dowle = function(dt) { # see EDIT later for more elegant solution
na.replace = function(v,value=0) { v[is.na(v)] = value; v }
for (i in names(dt))
eval(parse(text=paste("dt[,",i,":=na.replace(",i,"...
Learning Python from Ruby; Differences and Similarities
I know Ruby very well. I believe that I may need to learn Python presently. For those who know both, what concepts are similar between the two, and what are different?
...
How does std::move() transfer values into RValues?
...ct&& arg)
{
return static_cast<Object&&>(arg);
}
Now, you might wonder: do we even need the cast? The answer is: yes, we do. The reason is simple; named rvalue reference is treated as lvalue (and implicit conversion from lvalue to rvalue reference is forbidden by standard)....
Jackson JSON custom serialization for certain fields
...(Views.Web.class)
private String webField;
// getters/setters
...
..
}
Now we have to write custom json converter by simply extending HttpMessageConverter class from spring as:
public class CustomJacksonConverter implements HttpMessageConverter<Object>
{
public CustomJacksonC...
Why would iterating over a List be faster than indexing through it?
... item2 -> print item2 etc.
all in a single traversal, which is O(N).
Now, going to the other implementation of List which is ArrayList, that one is backed by a simple array. In that case both of the above traversals are equivalent, since an array is contiguous so it allows random jumps to arbi...
Explanation of strong and weak storage in iOS5
...ased off an analogy Malcom Crawford at Apple gave a few years back. Don't know where he got it.
– BJ Homer
Feb 13 '12 at 15:14
...
Is it better to call ToList() or ToArray() in LINQ queries?
... make it into Gen 2 then you may be better off paying the extra allocation now vs polluting the Gen 2 heap. IME though I rarely see this. It's much more common to see ToArray being passed immediately to another short lived LINQ query.
– JaredPar
May 1 '13 at 1...
Android REST client, Sample?
...ented in original answer still hold, as other answers point out, there are now libraries out there that make this task easier for you. More importantly, some of these libraries handle device configuration changes for you.
The original answer is retained below for reference. But please also take the ...
Error message “Forbidden You don't have permission to access / on this server” [closed]
...grp -R apache /username/ fixed the problem for me! but just like Edifice, now I can't access my home directory tree unless I chgrp back to my user. So now I need to change to my original user to pull in my changes via git. Then change back to apache to redeploy my server. Is this the only way?
...
When is it appropriate to use UDP instead of TCP? [closed]
...t handle that many sessions. This is a rare case today. In fact, there are now user-land TCP stacks that can be used so that the application writer may have finer grained control over the resources needed for that TCP state. Prior to 2003, UDP was really the only game in town.
One other case is for...