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How to convert a Django QuerySet to a list
...
Why not just call list() on the Queryset?
answers_list = list(answers)
This will also evaluate the QuerySet/run the query. You can then remove/add from that list.
...
What's a good way to extend Error in JavaScript?
...nvironments set the stack property, but fileName and lineNumber are practically useless to be used in inheritance.
So, the minimalistic approach is:
function MyError(message) {
this.name = 'MyError';
this.message = message;
this.stack = (new Error()).stack;
}
MyError.prototype = new Er...
Timeout a command in bash without unnecessary delay
...y, Bash does not support floating point arithmetic (sleep does),
therefore all delay/time values must be integers.
EOF
}
# Options.
while getopts ":t:i:d:" option; do
case "$option" in
t) timeout=$OPTARG ;;
i) interval=$OPTARG ;;
d) delay=$OPTARG ;;
*) printUsage...
Code Golf: Lasers
...is sitting on top of now. Since the laser emitter is to be treated like a wall, set this to be a wall to begin with.
if (tr/v<^/>v</) {
my $o;
$o .= "\n" while s/.$/$o .= $&, ""/meg;
tr,/\\,\\/, for $o, $s;
$_ = $o;
}
If the laser beam is pointing any way except right, rotate...
Principal component analysis in Python
...
Months later, here's a small class PCA, and a picture:
#!/usr/bin/env python
""" a small class for Principal Component Analysis
Usage:
p = PCA( A, fraction=0.90 )
In:
A: an array of e.g. 1000 observations x 20 variables, 1000 rows x 20 colum...
How do I uniquely identify computers visiting my web site?
..., fingerprints changed quite
rapidly, but even a simple heuristic was usually able to guess when a fingerprint was an “upgraded” version of a previously observed browser’s
fingerprint, with 99.1% of guesses correct and a false positive rate of only
0.86%.
We discuss what privacy thr...
AngularJS: Service vs provider vs factory
...get(). The constructor function is instantiated before the $get method is called - ProviderFunction is the function reference passed to module.provider.
Providers have the advantage that they can be configured during the module configuration phase.
See here for the provided code.
Here's a great fur...
Python multiprocessing pool.map for multiple arguments
...rmap method, which accepts a sequence of argument tuples. It then automatically unpacks the arguments from each tuple and passes them to the given function:
import multiprocessing
from itertools import product
def merge_names(a, b):
return '{} & {}'.format(a, b)
if __name__ == '__main__':...
How to split a string literal across multiple lines in C / Objective-C?
...
There are two ways to split strings over multiple lines:
Using \
All lines in C can be split into multiple lines using \.
Plain C:
char *my_string = "Line 1 \
Line 2";
Objective-C:
NSString *my_string = @"Line1 \
Line2";
Better approach
Th...
LINQ Select Distinct with Anonymous Types
...on of objects. The exact type isn't important. From it I want to extract all the unique pairs of a pair of particular properties, thusly:
...