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Can a shell script set environment variables of the calling shell? [duplicate]
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Your shell process has a copy of the parent's environment and no access to the parent process's environment whatsoever. When your shell process terminates any changes you've made to its environment are lost. Sourcing a script file is the most commonly used method for configuring a s...
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 can I test if a letter in a string is uppercase or lowercase using JavaScript?
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The answer by josh and maleki will return true on both upper and lower case if the character or the whole string is numeric. making the result a false result.
example using josh
var character = '5';
if (character == character.toUpperCase()) {...
HEAD and ORIG_HEAD in Git
What do these symbols refer to and what do they mean?
4 Answers
4
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phantomjs not waiting for “full” page load
...or if it takes longer than a second, it will still fail. Such inefficiency and unreliability is unbearable for professional work.
– CodeManX
Jul 15 '15 at 9:35
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sql query to return differences between two tables
...ies. I need to check three pieces of data in doing so, FirstName, LastName and Product.
12 Answers
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What's the difference between hard and soft floating point numbers?
... architecture" This can make sense for a library to be machine-independent and bit-exact (soft float) in accuracy-critical parts and fast (hard float) in parts where small deviations don't matter.
– PhilLab
May 29 '17 at 12:18
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Java to Clojure rewrite
...argish (50,000 single lines of code) Java application (a web app using JSP and servlets) in Clojure. Has anyone else got tips as to what I should watch out for?
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How to check if a variable is set in Bash?
...ar+x} is a parameter expansion which evaluates to nothing if var is unset, and substitutes the string x otherwise.
Quotes Digression
Quotes can be omitted (so we can say ${var+x} instead of "${var+x}") because this syntax & usage guarantees this will only expand to something that does not requ...
How to export revision history from mercurial or git to cvs?
...a project that uses cvs. We want to use a distributed vcs to make our work and when we finish or maybe every once in a while we want to commit our code and all of our revision history to cvs. We don't have write access to the project's cvs repo so we can't commit very frequently. What tool can we us...