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[ :Unexpected operator in shell programming [duplicate]
...et of sh syntax - the /bin/sh executable on your system may provide only standard sh functionality, in which []-style tests are not included.
– Tim
Aug 5 '10 at 1:17
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MySQL, better to insert NULL or empty string?
...a lot of different fields. Some of the fields are optional while some are mandatory. In my DB I have a table which holds all these values, is it better practice to insert a NULL value or an empty string into the DB columns where the user didn't put any data?
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Pass a data.frame column name to a function
I'm trying to write a function to accept a data.frame ( x ) and a column from it. The function performs some calculations on x and later returns another data.frame. I'm stuck on the best-practices method to pass the column name to the function.
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What are the minimum margins most printers can handle?
...ng real estate is a must but at the same time ensuring users printers can handle the tight margins is a must.
5 Answers
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What's the difference between a file descriptor and file pointer?
I want to know the difference between a file descriptor and file pointer.
9 Answers
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Resizing SVG in html?
So, I have an SVG file in HTML, and one of the things I've heard about the format is that it doesn't get all pixelated when you zoom in on it.
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Throwing the fattest people off of an overloaded airplane.
Let's say you've got an airplane, and it is low on fuel. Unless the plane drops 3000 pounds of passenger weight, it will not be able to reach the next airport. To save the maximum number of lives, we would like to throw the heaviest people off of the plane first.
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Difference between open and codecs.open in Python
...open is an alias for the open() built-in. So io.open() works in Python 2.6 and all later versions, including Python 3.4. See docs: http://docs.python.org/3.4/library/io.html
Now, for the original question: when reading text (including "plain text", HTML, XML and JSON) in Python 2 you should always ...
How to find patterns across multiple lines using grep?
I want to find files that have "abc" AND "efg" in that order, and those two strings are on different lines in that file. Eg: a file with content:
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Django South - table already exists
I am trying to get started with South. I had an existing database and I added South ( syncdb , schemamigration --initial ).
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