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Is R's apply family more than syntactic sugar?
... This is a little off topic, but for this specific example, data.table is even faster and I think "easier". library(data.table) dt<-data.table(X,Y,Z,key=c("Y,Z")) system.time(dt[,list(X_mean=mean(X)),by=c("Y,Z")])
– dnlbrky
Feb 22 '13 at 4:01
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How do I restore a dump file from mysqldump?
...mmand prompt (in Windows) and cd to the directory where the mysql.exe executable is (you may have to look around a bit for it, it'll depend on how you installed mysql, i.e. standalone or as part of a package like WAMP). Once you're in that directory, you should be able to just type the command as I...
What should I do if two libraries provide a function with the same name generating a conflict?
... bit hackish, but all you'd be doing is changing the strings in the symbol table. No real functional harm in that.
– Evan Teran
Mar 24 '09 at 17:52
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Django 1.7 - makemigrations not detecting changes
...ion module and now it's working. makemigrations will not work on unmanaged tables (Which is obvious in hindsight)
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Change SQLite default settings
we know when type .mode column let me see tables like column
And .headers on , we can see the header of tables.
But I want to know if there is any way make the two default settings?
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Does opacity:0 have exactly the same effect as visibility:hidden
...s* No No
display: none Yes No No
* Yes inside a table element, otherwise No.
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Is PHP compiled or interpreted?
...PHP compiler's job is to parse your PHP code and convert it into a form suitable for the runtime engine. Among its tasks:
Ignore comments
Resolve variables, function names, and so forth and create the symbol table
Construct the abstract syntax tree of your program
Write the bytecode
Depending on...
How to allow remote connection to mysql
... line without the # is this : sql_mode=NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES
– Leo
Feb 8 '13 at 19:11
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Best database field type for a URL
I need to store a url in a MySQL table. What's the best practice for defining a field that will hold a URL with an undetermined length?
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When should I use Kruskal as opposed to Prim (and vice versa)?
...s an obscure term to use, for example what is the "average size" of a hash table? no idea.
– yairchu
Jul 29 '09 at 11:28
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