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Does adding a duplicate value to a HashSet/HashMap replace the previous value

...do a check on the backing HashMap to see if the key already exists before calling put on the backing map? – mystarrocks Jun 9 '14 at 21:36 ...
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pandas dataframe columns scaling with sklearn

...and I'd like to apply sklearn's min_max_scaler to some of the columns. Ideally, I'd like to do these transformations in place, but haven't figured out a way to do that yet. I've written the following code that works: ...
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Truncating floats in Python

...o the binary value stored in the computer's memory, not the string you actually typed into the source code.1 If you decode the sequence of bits back into a decimal number, again using the IEEE 64-bit floating-point format, you get 0.2999999999999999888977697537484345957637... so a naive implemen...
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Allowed characters in Linux environment variable names

What characters are allowed in Linux environment variable names? My cursory search of man pages and the web did only produce information about how to work with variables, but not which names are allowed. ...
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Zero-pad digits in string

... First of all, your description is misleading. Double is a floating point data type. You presumably want to pad your digits with leading zeros in a string. The following code does that: $s = sprintf('%02d', $digit); For more informa...
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Automatic HTTPS connection/redirect with node.js/express

...ng to get HTTPS set up with a node.js project I'm working on. I've essentially followed the node.js documentation for this example: ...
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What are the special dollar sign shell variables?

... $3, ... are the positional parameters. "$@" is an array-like construct of all positional parameters, {$1, $2, $3 ...}. "$*" is the IFS expansion of all positional parameters, $1 $2 $3 .... $# is the number of positional parameters. $- current options set for the shell. $$ pid of the current shell (...
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How to terminate the script in JavaScript?

... JavaScript equivalent for PHP's die. BTW it just calls exit() (thanks splattne): function exit( status ) { // http://kevin.vanzonneveld.net // + original by: Brett Zamir (http://brettz9.blogspot.com) // + input by: Paul // + bugfixed by: Hyam Singer...
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Javascript how to split newline

... or, more specifically, /\r?\n/ ... I think using | (or) would interleave empty results for CRLF line endings. – Dusty Oct 5 '16 at 16:39 ...
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C library function to perform sort

... qsort() is the function you're looking for. You call it with a pointer to your array of data, the number of elements in that array, the size of each element and a comparison function. It does its magic and your array is sorted in-place. An example follows: #include <st...