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Convert data.frame column to a vector?
...a frame is a list. When you subset a data frame using the name of a column and [, what you're getting is a sublist (or a sub data frame). If you want the actual atomic column, you could use [[, or somewhat confusingly (to me) you could do aframe[,2] which returns a vector, not a sublist.
So try run...
add created_at and updated_at fields to mongoose schemas
Is there a way to add created_at and updated_at fields to a mongoose schema, without having to pass them in everytime new MyModel() is called?
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Entity Framework Migrations renaming tables and columns
I renamed a a couple entities and their navigation properties and generated a new Migration in EF 5. As is usual with renames in EF migrations, by default it was going to drop objects and recreate them. That isn't what I wanted so I pretty much had to build the migration file from scratch.
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How can I specify working directory for popen
Is there a way to specify the running directory of command in Python's subprocess.Popen() ?
1 Answer
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How do I limit the number of rows returned by an Oracle query after ordering?
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How can we get the LIMIT and OFFSET in Oracle 11G ?
– Pra_A
Jun 21 at 13:37
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Is there a list of Pytz Timezones?
...util.tz provides similar functionalities but uses the OS timezone database and has no such problems.
– Yongwei Wu
Feb 1 '18 at 15:17
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What's up with Java's “%n” in printf?
I'm reading Effective Java and it uses %n for the newline character everywhere. I have used \n rather successfully for newline in Java programs.
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resizes wrong; appears to have unremovable `min-width: min-content`
... (25 Sept 2017)
The Firefox bug described below is fixed as of Firefox 53 and the link to this answer has finally been removed from Bootstrap's documentation.
Also, my sincere apologies to the Mozilla contributors who had to block removing support for -moz-document partly due to this answer.
The ...
Open Source Java Profilers [closed]
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The VisualVM profiler is a stand-alone version of the one in NetBeans. It is a VERY good start.
– Thorbjørn Ravn Andersen
Jun 4 '09 at 6:06
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Database Structure for Tree Data Structure
...o-nested-sets
There are other models as well, including materialized path and nested sets:
http://communities.bmc.com/communities/docs/DOC-9902
Joe Celko has written a book on this subject, which is a good reference from a general SQL perspective (it is mentioned in the nested set article link abo...