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How to deal with “data of class uneval” error from ggplot2?

... No its not! and yes you will! Glad I could steer you in the right direction and now its here for posterity. – Justin May 10 '13 at 16:39 ...
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How to exclude this / current / dot folder from find “type d”

... because of the !. To exclude other directories, this will golf less well and requires a variable for DRYness: D="long_name" find "$D" ! -path "$D" -type d My decision tree between ! and -mindepth: script? Use ! for portability. interactive session on GNU? exclude .? Throw a coin. exclude lo...
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How to extract epoch from LocalDate and LocalDateTime?

... The classes LocalDate and LocalDateTime do not contain information about the timezone or time offset, and seconds since epoch would be ambigious without this information. However, the objects have several methods to convert them into date/time obj...
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SQL: How to properly check if a record exists

...optimize SELECT COUNT(*) anyway, so while there is a difference in theory (and older databases), you shouldn't notice any difference in practice. share | improve this answer | ...
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How to get just the parent directory name of a specific file

... Use File's getParentFile() method and String.lastIndexOf() to retrieve just the immediate parent directory. Mark's comment is a better solution thanlastIndexOf(): file.getParentFile().getName(); These solutions only works if the file has a parent file (e...
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How to describe “object” arguments in jsdoc?

...bject member which is option ? I mean my user object should have username, and can have full name. so how do I specify that full name is optional – Yash Kumar Verma Apr 13 at 9:25 ...
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What is the canonical way to trim a string in Ruby without creating a new string?

...e.strip! The #strip! method will return nil if it didn't strip anything, and the variable itself if it was stripped. According to Ruby standards, a method suffixed with an exclamation mark changes the variable in place. Hope this helps. Update: This is output from irb to demonstrate: >> ...
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Removing duplicate rows in vi?

... a long list of entries (one on each line). Some of these are duplicates, and I would like to know if it is possible (and if so, how) to remove any duplicates. I am interested in doing this from within vi/vim, if possible. ...
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How do I get the parent directory in Python?

...is an entire RFC 1808 written to address the issue of relative path in URI and all the subtlety of the presence and absence of a trailing /. If you know of any documentation that says they should be treated equivalent in general please point it out. – Wai Yip Tung ...
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Define all functions in one .R file, call them from another .R file. How, if possible?

...If abc.R is: fooABC <- function(x) { k <- x+1 return(k) } and xyz.R is: fooXYZ <- function(x) { k <- fooABC(x)+1 return(k) } then this will work: > source("abc.R") > source("xyz.R") > fooXYZ(3) [1] 5 > Even if there are cyclical dependencies, this wi...