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How to see if an object is an array without using reflection?
...Object is an array without using reflection?
And how can I iterate through all items without using reflection?
6 Answers
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Check for installed packages before running install.packages() [duplicate]
...h several users on different computers. One of its lines contains the install.packages("xtable") command.
16 Answers
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Simulate limited bandwidth from within Chrome?
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If you are running Linux, the following command is really useful for this:
trickle -s -d 50 -w 100 firefox
The -s tells the command to run standalone, the -d 50 tells it to limit bandwidth to 50 KB/s, the -w 100 set the peak detection window size to 100 KB. firefox tells the...
What is sharding and why is it important?
... be possible to infer the appropriate shard membership easily and automatically, and query only the relevant shard.
Some more information about sharding:
Firstly, each database server is identical, having the same table structure. Secondly, the data records are logically split up in a sharded ...
Quick unix command to display specific lines in the middle of a file?
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Or more specifically 10 lines before: grep -B 10 ... Or 10 lines after: grep -A 10 ...
– Boy Baukema
May 21 '12 at 11:14
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How to check if a file is empty in Bash?
I have a file called diff.txt. Want to check if it is empty. Did something like this but couldn't get it working.
10 Answe...
How to create a database from shell command?
...for something like createdb in PostgreSQL or any other solution that would allow me to create database with a help of a shell command. Any hints?
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How to show only next line after the matched one?
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For anyone who really wanted a grep -A2 equivalent (which is what I needed), getline just eats the line and goes on to the next. So what worked for me was literally just awk '/blah/{getline; getline; print}' logfile
– A...
How can you find out which process is listening on a port on Windows?
...Note Dane's recommendation for TCPView. It looks very useful!
-a Displays all connections and listening ports.
-b Displays the executable involved in creating each connection or listening port. In some cases well-known executables host multiple independent components, and in these cases the sequen...
How to map atan2() to degrees 0-360
...swered Aug 21 '09 at 10:20
erikkallenerikkallen
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