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Fastest way to replace NAs in a large data.table
....805 12.301 134.985
system.time(a_andrie = f_andrie(dt1))
Error: cannot allocate vector of size 305.2 Mb
Timing stopped at: 14.541 7.764 68.285
system.time(f_dowle(dt1))
user system elapsed
7.452 4.144 19.590 # EDIT has faster than this
identical(a_gdata, dt1)
[1] TRUE
Note th...
What is the recommended approach towards multi-tenant databases in MongoDB?
...ecifics of the database design.
Collections (or buckets or however they call it in different DBs) are not the same thing as security schemas in RDBMS despite they behave as container for documents they are useless for applying good tenant separation. I couldn't find NoSQL database that can apply s...
How do I add a submodule to a sub-directory?
...op-level requirement
Use the new rev-parse --prefix option to process all paths given to the submodule command, dropping the requirement that it be run from the top-level of the repository.
Since the interpretation of a relative submodule URL depends on whether or not "remote.origin.url" i...
Operator overloading in Java
...
You are saying we cant create wrapper in java? Such as SmallInteger like Integer?
– huseyin tugrul buyukisik
Sep 12 '12 at 10:58
...
Regex group capture in R with multiple capture-groups
...
and str_match_all() to match all groups in a regex
– smci
Mar 26 '14 at 15:49
...
Number of lines in a file in Java
...iles, sometimes I only need to know the number of lines in these files, usually I open them up and read them line by line until I reach the end of the file
...
How do you properly use namespaces in C++?
...
Namespaces are packages essentially. They can be used like this:
namespace MyNamespace
{
class MyClass
{
};
}
Then in code:
MyNamespace::MyClass* pClass = new MyNamespace::MyClass();
Or, if you want to always use a specific namespace, you can d...
How to use Python's pip to download and keep the zipped files for a package?
...the pip command to download a package (and its dependencies), but keep all of the zipped files that get downloaded (say, django-socialregistration.tar.gz) - is there a way to do that?
...
Convert Bitmap to File
...eger, String> {
Context context;
Bitmap bitmap;
String path_external = Environment.getExternalStorageDirectory() + File.separator + "temporary_file.jpg";
public fileFromBitmap(Bitmap bitmap, Context context) {
this.bitmap = bitmap;
this.context= context;
}
...
Log all queries in mysql
... following in your my.cnf file:
log = log_file_name
Either one will log all queries to log_file_name.
You can also log only slow queries using the --log-slow-queries option instead of --log. By default, queries that take 10 seconds or longer are considered slow, you can change this by setting l...