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Cleaner way to update nested structures
...scalaz.TreeLoc). It turns out that the structure of the zipper is automatically derivable from the original data structure, in a manner that resembles symbolic differentiation of an algebraic expression.
But how does this help you with your Scala case classes? Well, Lukas Rytz recently prototyped a...
Detect & Record Audio in Python
...
Great example! Really useful when I tried to wrap my head around how to record voice using Python. One quick question I had is whether there is a way to define the time period of the recording. Now it records a word? Can I play with it and ha...
Does C have a “foreach” loop construct?
Almost all languages have a foreach loop or something similar. Does C have one? Can you post some example code?
12 Answer...
What encoding/code page is cmd.exe using?
...e and other programs
print gibberish, and sometimes they do not.
First of all, Unicode characters will only display if the
current console font contains the characters. So use
a TrueType font like Lucida Console instead of the default Raster Font.
But if the console font doesn’t contain the char...
Convert base-2 binary number string to int
... (as suggested by the >>> prompt), you don't need to use print at all. The OP's hypothetical example didn't. So it really should be identical in Python 2 and 3.
– John Y
Jul 12 '16 at 22:36
...
Check if two unordered lists are equal [duplicate]
...has a built-in datatype for an unordered collection of (hashable) things, called a set. If you convert both lists to sets, the comparison will be unordered.
set(x) == set(y)
Documentation on set
EDIT: @mdwhatcott points out that you want to check for duplicates. set ignores these, so you need ...
Hashing a dictionary?
...e hash():
hash(frozenset(my_dict.items()))
This is much less computationally intensive than generating the JSON string or representation of the dictionary.
UPDATE: Please see the comments below, why this approach might not produce a stable result.
...
How to add a progress bar to a shell script?
...}
done
If you already have a loop which does a lot of work, you can call the
following function at the beginning of each iteration to update the
spinner:
sp="/-\|"
sc=0
spin() {
printf "\b${sp:sc++:1}"
((sc==${#sp})) && sc=0
}
endspin() {
printf "\r%s\n" "$@"
}
until wor...
How to calculate the bounding box for a given lat/lng location?
...
I suggest to approximate locally the Earth surface as a sphere with radius given by the WGS84 ellipsoid at the given latitude. I suspect that the exact computation of latMin and latMax would require elliptic functions and would not yield an appreciable ...
What is the most efficient/elegant way to parse a flat table into a tree?
...
Now that MySQL 8.0 supports recursive queries, we can say that all popular SQL databases support recursive queries in standard syntax.
WITH RECURSIVE MyTree AS (
SELECT * FROM MyTable WHERE ParentId IS NULL
UNION ALL
SELECT m.* FROM MyTABLE AS m JOIN MyTree AS t ON m.ParentI...