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How can I get the current network interface throughput statistics on Linux/UNIX? [closed]
Tools such as MRTG provide network throughput / bandwidth graphs for the current network utilisation on specific interfaces, such as eth0. How can I return that information at the command line on Linux/UNIX?
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Editing dictionary values in a foreach loop
I am trying to build a pie chart from a dictionary. Before I display the pie chart, I want to tidy up the data. I'm removing any pie slices that would be less than 5% of the pie and putting them in a "Other" pie slice. However I'm getting a Collection was modified; enumeration operation may not exe...
dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
When using summarise with plyr 's ddply function, empty categories are dropped by default. You can change this behavior by adding .drop = FALSE . However, this doesn't work when using summarise with dplyr . Is there another way to keep empty categories in the result?
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~x + ~y == ~(x + y) is always false?
Does this code always evaluate to false? Both variables are two's complement signed ints.
11 Answers
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ActiveRecord: size vs count
In Rails, you can find the number of records using both Model.size and Model.count . If you're dealing with more complex queries is there any advantage to using one method over the other? How are they different?
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Catching error codes in a shell pipe
I currently have a script that does something like
4 Answers
4
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How to open, read, and write from serial port in C?
I am a little bit confused about reading and writing to a serial port. I have a USB device in Linux that uses the FTDI USB serial device converter driver. When I plug it in, it creates: /dev/ttyUSB1.
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How do I round to the nearest 0.5?
I have to display ratings and for that i need increments as follows:
9 Answers
9
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How to configure PostgreSQL to accept all incoming connections
I've got a PostgreSQL data base that I'd like to configure to accept all incoming connections regardless of the source IP address. How can this be configured in the pg_hba.conf file? I'm using postgreSQL version 8.4.
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What does multicore assembly language look like?
Once upon a time, to write x86 assembler, for example, you would have instructions stating "load the EDX register with the value 5", "increment the EDX" register, etc.
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