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What are the respective advantages/limitations of Amazon RDS vs. EC2 with MySQL? [closed]
...ole is fantastic and it's easy to upgrade instances. High availability and read only slaves are a click away. It's REALLY awesome.
Short answer: Go with RDS. Still on the fence? Go with RDS!!! if you enjoy headaches and tuning every last little bit for maximum performance, then you can consider EC2...
How do I make a list of data frames?
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The other answers show you how to make a list of data.frames when you already have a bunch of data.frames, e.g., d1, d2, .... Having sequentially named data frames is a problem, and putting them in a list is a good fix, but best practice is to avoid having a bunch of data.frames not in a list in ...
How to check if a file is empty in Bash?
...efaults set for ls that use the long format (like me) and the shell will already expand *.txt on its own. Just do for file in *.txt instead.
– Lilith
Jun 26 '18 at 17:19
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How can I read command line parameters from an R script?
...s$options
file <- args$args
if(opt$count_lines) {
print(paste(length(readLines(file)) * opt$factor))
}
Given an arbitrary file blah.txt with 23 lines.
On the command line:
Rscript script.R -h outputs
Usage: script.R [options] file
Options:
-n, --count_lines
Count...
How get integer value from a enum in Rails?
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Rails < 5
Another way would be to use read_attribute():
model = Model.find(123)
model.read_attribute('sale_info')
Rails >= 5
You can use read_attribute_before_type_cast
model.read_attribute_before_type_cast(:sale_info)
=> 1
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What is the best comment in source code you have ever encountered? [closed]
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I read all comments from top to bottom, wondering what people meant, when they say the "cracked up, reading this one" or "cracked up, reading that one". Well. I just cracked up reading this one...
– Daren ...
What does the property “Nonatomic” mean?
...omic, and you generate the accessors using @synthesize, then if multiple threads try to change/read the property at once, badness can happen. You can get partially-written values or over-released/retained objects, which can easily lead to crashes. (This is potentially a lot faster than an atomic acc...
What are the benefits to marking a field as `readonly` in C#?
What are the benefits of having a member variable declared as read only? Is it just protecting against someone changing its value during the lifecycle of the class or does using this keyword result in any speed or efficiency improvements?
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Scanner is skipping nextLine() after using next() or nextFoo()?
I am using the Scanner methods nextInt() and nextLine() for reading input.
19 Answers
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sed one-liner to convert all uppercase to lowercase?
...e to lowercase, using sed . That means that the first sentence would then read, 'i have a textfile in which some words are printed in all caps.'
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