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Is there an R function for finding the index of an element in a vector?
In R, I have an element x and a vector v . I want to find the first index of an element in v that is equal to x . I know that one way to do this is: which(x == v)[[1]] , but that seems excessively inefficient. Is there a more direct way to do it?
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Does name length impact performance in Redis?
...ET (10 keys)",cmd,len);
free(cmd);
- len = redisFormatCommand(&cmd,"SET foo:rand:000000000000 %s",data);
+ len = redisFormatCommand(&cmd,"SET foo %s",data);
benchmark("SET",cmd,len);
free(cmd);
- len = redisFormatCommand(&cmd,"GET foo:ran...
JavaScript data grid for millions of rows [closed]
...s set to the total height of all the rows. The rows are still being added and removed as the user is scrolling, but the scrolling itself is done by the browser. That allows it to be very fast yet smooth (onscroll events are notoriously slow). The caveat is that there are bugs/limits in the browse...
Cosmic Rays: what is the probability they will affect a program?
Once again I was in a design review, and encountered the claim that the probability of a particular scenario was "less than the risk of cosmic rays" affecting the program, and it occurred to me that I didn't have the faintest idea what that probability is.
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What is the difference between “Form Controls” and “ActiveX Control” in Excel 2010?
...two kind of controls that can be inserted into a document: Form Controls and ActiveX Controls .
4 Answers
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stopPropagation vs. stopImmediatePropagation
What's the difference between event.stopPropagation() and event.stopImmediatePropagation() ?
9 Answers
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What kind of virtual machine is BEAM (the Erlang VM)?
From what I understand a virtual machine falls into two categories either "system virtual machine" or a "process virtual machine". It's kind of fuzzy to me where BEAM lies. Is there another kind of virtual machine I am not aware of?
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Difference between database and schema
What's the difference between a Database and a Schema in SQL Server? Both are the containers of tables and data.
5 Answers
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MongoDB and “joins” [duplicate]
...ll only be evaluated when needed. A join (in a SQL database) on the other hand will resolve relationships and return them as if they were a single table (you "join two tables into one").
You can read more about DBRef here:
http://docs.mongodb.org/manual/applications/database-references/
There are ...
How do I detect a click outside an element?
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This breaks standard behaviour of many things, including buttons and links, contained within #menucontainer. I am surprised this answer is so popular.
– Art
Jun 12 '10 at 8:00
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