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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,"...
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
...
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...
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?
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Conditionally use 32/64 bit reference when building in Visual Studio
...to switch configurations and have the correct reference used, but I don't know how to tell Visual Studio to use the architecture-appropriate dependency.
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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...
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...
What algorithm can be used for packing rectangles of different sizes into the smallest rectangle pos
... I was just playing with something like that on a bit of paper, right now looks fairly optimal in most cases, even without rotating the rectangles or anything
– Fire Lancer
Jul 31 '09 at 16:37
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Quickly reading very large tables as dataframes
... implementation that would slow things down. In my case, I am assuming I know the types of the columns ahead of time, the table does not contain any column headers or row names, and does not have any pathological characters that I have to worry about.
...
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 ...