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Drop rows with all zeros in pandas data frame
I can use pandas dropna() functionality to remove rows with some or all columns set as NA 's. Is there an equivalent function for dropping rows with all columns having value 0?
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jQuery deferreds and promises - .then() vs .done()
I've been reading about jQuery deferreds and promises and I can't see the difference between using .then() & .done() for successful callbacks. I know Eric Hynds mentions that .done() and .success() map to the same functionality but I'm guessing so does .then() as all the callbacks are al...
What is Unicode, UTF-8, UTF-16?
What's the basis for Unicode and why the need for UTF-8 or UTF-16?
I have researched this on Google and searched here as well but it's not clear to me.
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How can I repeat a character in Bash?
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You can use:
printf '=%.0s' {1..100}
How this works:
Bash expands {1..100} so the command becomes:
printf '=%.0s' 1 2 3 4 ... 100
I've set printf's format to =%.0s which means that it will always print a single = no matter what argument it is given. Therefore it prints 100 =s.
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How to strip all non-alphabetic characters from string in SQL Server?
...t dbo.RemoveNonAlphaCharacters('abc1234def5678ghi90jkl')
Once you understand the code, you should see that it is relatively simple to change it to remove other characters, too. You could even make this dynamic enough to pass in your search pattern.
Hope it helps.
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F# development and unit testing?
... first functional language. I have been working quasi-exclusively with C#, and enjoy a lot how F# leads me to re-think how I write code. One aspect I find a bit disorienting is the change in the process of writing code. I have been using TDD for years in C# now, and really appreciate to have unit te...
Is there a difference between foreach and map?
...n a particular language, but is there a difference between a map operation and a foreach operation? Or are they simply different names for the same thing?
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Temporarily put away uncommitted changes in Subversion (a la “git-stash”)
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When I've got uncommitted changes from one task in my working copy and I need to switch to another task, I do one of two things:
Check out a new working copy for the second task.
or
Start a branch:
workingcopy$ svn copy CURRENT_URL_OF_WORKING_COPY SOME_BRANCH
workingcopy$ svn switch SOME...
Regular expression that matches valid IPv6 addresses
...ular expressions, so I wrote one that works with POSIX regular expressions and PERL regular expressions.
It should match:
IPv6 addresses
zero compressed IPv6 addresses (section 2.2 of rfc5952)
link-local IPv6 addresses with zone index (section 11 of rfc4007)
IPv4-Embedded IPv6 Address (section 2 ...
Test if characters are in a string
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@GregSnow -- Tried system.time(a <- grepl("abc", vec)) and system.time(a <- grepl("abc", vec, fixed=TRUE)), and fixed=TRUE is still, if anything slightly slower. The difference isn't appreciable with these short strings, but fixed=TRUE still doesn't seem to be faster. Thanks ...