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Using try vs if in python
...er LBYL style ("look before you leap"). To me, it's a matter of efficiency and readability.
In your example (say that instead of returning a list or an empty string, the function were to return a list or None), if you expect that 99 % of the time result will actually contain something iterable, I'd...
Where should signal handlers live in a django project?
...started implementing signal listeners in a django project. While I understand what they are and how to use them. I am having a hard time figuring out where I should put them. The documentation from the django site has this to say:
...
read.csv warning 'EOF within quoted string' prevents complete reading of file
...112,544 rows. When I read it into R with read.csv I only get 56,952 rows and this warning:
8 Answers
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How to reset radiobuttons in jQuery so that none is checked
...e note 2 below).
Note 1: it is important that the second argument be false and not "false" since "false" is not a falsy value. i.e.
if ("false") {
alert("Truthy value. You will see an alert");
}
Note 2: As of jQuery 1.6.0, there are now two similar methods, .attr and .prop that do two related b...
Bash tool to get nth line from a file
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head and pipe with tail will be slow for a huge file. I would suggest sed like this:
sed 'NUMq;d' file
Where NUM is the number of the line you want to print; so, for example, sed '10q;d' file to print the 10th line of file.
Ex...
Unix command-line JSON parser? [closed]
...
You can use this command-line parser (which you could put into a bash alias if you like), using modules built into the Perl core:
perl -MData::Dumper -MJSON::PP=from_json -ne'print Dumper(from_json($_))'
...
How to get the part of a file after the first line that matches a regular expression?
...g the TERMINATE regular expression (like grep) to the end of the file ($), and p is the print command which prints the current line.
This will print from the line that follows the line matching TERMINATE till the end of the file:
(from AFTER the matching line to EOF, NOT including the matching line...
Efficient Algorithm for Bit Reversal (from MSB->LSB to LSB->MSB) in C
... trade off memory for speed (assuming your L1 Data Cache is large enough), and reverse 16 bits at a time with a 64K-entry lookup table.
Others
Simple
unsigned int v; // input bits to be reversed
unsigned int r = v & 1; // r will be reversed bits of v; first get LSB of v
int s = sizeof(v...
Haskell testing workflow
I just started a new Haskell project and wanted to set up a good testing workflow from the beginning. It seems like Haskell has a lot of excellent and unique testing tools and many different ways to integrate them.
...
Current time formatting with Javascript
...oneOffset() - Returns the number of minutes between the machine local time and UTC.
There are no built-in methods allowing you to get localized strings like "Friday", "February", or "PM". You have to code that yourself. To get the string you want, you at least need to store string representations...