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Ubuntu rails install fails on zlib
...0 as my dev box; it's my first serious foray into Linux as a daily-use OS, and I'm having a hard time getting Rails going. I have followed a number of tutorials which all seem to work fine, but when I try and use gem install or gem update on anything, I get an error that looks like this:
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Quick-and-dirty way to ensure only one instance of a shell script is running at a time
What's a quick-and-dirty way to make sure that only one instance of a shell script is running at a given time?
40 Answers
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Passing command line arguments to R CMD BATCH
.... I am now at the point where I would like to pass an argument to the command, but am having some issues getting it working. If I do R CMD BATCH my_script.R blabla then blabla becomes the output file, rather than being interpreted as an argument available to the R script being executed.
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How to convert floats to human-readable fractions?
...y what you are asking for. Its based on the theory of continued fractions and very fast and fairly compact.
I have used versions of this customized for specific numerator and denominator limits.
/*
** find rational approximation to given real number
** David Eppstein / UC Irvine / 8 Aug 1993
**
*...
java.lang.UnsupportedClassVersionError: Bad version number in .class file?
... suggestions on the web indicate that the code was compiled in one version and executed in another version (new on old). However, I only have one version of JRE on my system. If I run the commands:
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Counting inversions in an array
... find all inversion pairs such that A[i] > A[j] . I'm using merge sort and copying array A to array B and then comparing the two arrays, but I'm having a difficult time seeing how I can use this to find the number of inversions. Any hints or help would be greatly appreciated.
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Why is [1,2] + [3,4] = “1,23,4” in JavaScript?
...d for arrays.
What happens is that Javascript converts arrays into strings and concatenates those.
Update
Since this question and consequently my answer is getting a lot of attention I felt it would be useful and relevant to have an overview about how the + operator behaves in general also.
So, h...
Difference between `set`, `setq`, and `setf` in Common Lisp?
What is the difference between "set", "setq", and "setf" in Common Lisp?
6 Answers
6
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Is there a difference between YES/NO,TRUE/FALSE and true/false in objective-c?
Simple question really; is there a difference between these values (and is there a difference between BOOL and bool)? A co-worker mentioned that they evaluate to different things in Objective-C, but when I looked at the typedefs in their respective .h files, YES/TRUE/true were all defined as 1 an...
How to split a string and assign it to variables
In Python it is possible to split a string and assign it to variables:
9 Answers
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