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Handling a colon in an element ID in a CSS selector [duplicate]
...the beginning of a pseudo-element to the browser so it gets marked invalid and ignored. Is there anyway to escape the colon or something?
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setup.py examples?
...ackages on the Python Package Index. Just download the tarball, unpack it, and have a look at the setup.py file. Or even better, only bother looking through packages that list a public source code repository such as one hosted on GitHub or BitBucket. You're bound to run into one on the front page.
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How can I check if a directory exists in a Bash shell script?
What command can be used to check if a directory exists or not, within a Bash shell script?
35 Answers
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How can you use an object's property in a double-quoted string?
... # yields "abc.Length"
"$($bar.Length)" # yields "3"
PowerShell only expands variables in those cases, nothing more. To force evaluation of more complex expressions, including indexes, properties or even complete calculations, you have to enclose those in the subexpression operator $( ) which cau...
unix - head AND tail of file
Say you have a txt file, what is the command to view the top 10 lines and bottom 10 lines of file simultaneously?
20 Answer...
Speed up the loop operation in R
... over a data.frame object. It simply adds a new column to a data.frame and accumulates something. (simple operation). The data.frame has roughly 850K rows. My PC is still working (about 10h now) and I have no idea about the runtime.
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How do I update if exists, insert if not (AKA “upsert” or “merge”) in MySQL?
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@blub: If you create a unique key on geb and topic it will work (ALTER TABLE table ADD UNIQUE geb_by_topic (geb, topic)).
– chaos
Aug 2 '09 at 13:43
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How to write a cron that will run a script every day at midnight?
I have heard crontab is a good choice, but how do I write the line and where do I put it on the server?
6 Answers
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Big-oh vs big-theta [duplicate]
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Big-O is an upper bound.
Big-Theta is a tight bound, i.e. upper and lower bound.
When people only worry about what's the worst that can happen, big-O is sufficient; i.e. it says that "it can't get much worse than this". The tighter the bound the better, of course, but a tight bound isn't...
Rebasing a branch including all its children
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Doesn't the "git branch" command output a star before the current branch, screwing up this script if one of the branches to rebase is currently checked out?
– Mark Lodato
Dec 20 '12 at 21:38
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