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Getting the difference between two sets
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Try this
test2.removeAll(test1);
Set#removeAll
Removes from this set all of its elements that are contained in the specified collection (optional operation). If the specified collection is also a set, this operation effectively modifies this set so that its value is the asymmetri...
Using the rJava package on Win7 64 bit with R
...windows-i586.exe and jdk-8u172-windows-x64.exe and then the binary package from CRAN:
install.packages("rJava")
The binary package from CRAN should pick up on the jvm by itself. Experts only: to build rJava from source, you need the --merge-multiarch flag:
install.packages('rJava', type = 'sour...
Does Python optimize tail recursion?
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Or if you're going to transform it like that - just: from operator import add; reduce(add, xrange(n + 1), csum) ?
– Jon Clements♦
Nov 27 '12 at 20:10
38
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Postgresql not creating db with “createdb” as superuser, yet not outputting errors [duplicate]
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createdb is a command line utility which you can run from bash and not from psql.
To create a database from psql, use the create database statement like so:
create database [databasename];
Note: be sure to always end your SQL statements with ;
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java.nio.file.Path for a classpath resource
Is there an API to get a classpath resource (e.g. what I'd get from Class.getResource(String) ) as a java.nio.file.Path ? Ideally, I'd like to use the fancy new Path APIs with classpath resources.
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Can dplyr package be used for conditional mutating?
...mark might not be quite fair - in addition to not receiving the same input from the 2nd iteration forward (which might affect timing since DT$g is already allocated?), the result also propagates back to ans1 and therefore might (if R's optimizer deems it necessary? Not sure on this...) avoid another...
Fastest Way of Inserting in Entity Framework
...he context after SaveChanges and create a new one. This clears the context from all entites, SaveChanges doesn't do that, the entities are still attached to the context in state Unchanged. It is the growing size of attached entities in the context what slows down the insertion step by step. So, it i...
Entity Framework rollback and remove bad migration
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You have 2 options:
You can take the Down from the bad migration and put it in a new migration (you will also need to make the subsequent changes to the model). This is effectively rolling up to a better version.
I use this option on things that have gone to multip...
How to tell where a header file is included from?
... answer. Only unfortunate problem is that I couldn't get it to stop Clang from trying to compile the file normally, so I ended up using clang++ -MM -H (which is a slightly useful combination).
– rookie1024
Feb 17 '17 at 17:36
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How to resolve git stash conflict without commit?
.... You can execute it without any parameters and Git will remove everything from the index. You don't have to execute git add before.
Finally, remove the stash with git stash drop, because Git doesn't do that on conflict.
Translated to the command-line:
$ git stash pop
# ...resolve conflict(s)
$...