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Search and replace in bash using regular expressions
...is method, i.e. perl, awk, e.g.:
echo "$MYVAR" | perl -pe 's/[a-zA-Z]/X/g and s/[0-9]/N/g'
This may allow you to do more creative matches... For example, in the snip above, the numeric replacement would not be used unless there was a match on the first expression (due to lazy and evaluation). A...
Explicitly calling return in a function or not
...
Question was: Why is not (explicitly) calling return faster or better, and thus preferable?
There is no statement in R documentation making such an assumption.
The main page ?'function' says:
function( arglist ) expr
return(value)
Is it faster without calling return?
Both function() and re...
How to convert JSON data into a Python object
...
UPDATE
With Python3, you can do it in one line, using SimpleNamespace and object_hook:
import json
from types import SimpleNamespace
data = '{"name": "John Smith", "hometown": {"name": "New York", "id": 123}}'
# Parse JSON into an object with attributes corresponding to dict keys.
x = json.lo...
NumPy: function for simultaneous max() and min()
numpy.amax() will find the max value in an array, and numpy.amin() does the same for the min value. If I want to find both max and min, I have to call both functions, which requires passing over the (very big) array twice, which seems slow.
...
How can I set the color of a selected row in DataGrid
... needed. Allowed me to continue to reference an existing style for the DG and change the background brush for a selected row.
– Gatmando
Jan 6 '11 at 14:32
5
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Is there a valid reason for enforcing a maximum width of 80 characters in a code file, this day and
... column rule:
To avoid wrapping when copying code into email, web pages, and books.
To view multiple source windows side-by-side or using a side-by-side diff viewer.
To improve readability. Narrow code can be read quickly without having to scan your eyes from side to side.
I think the last point...
Get IP address of visitors using Flask for Python
I'm making a website where users can log on and download files, using the Flask micro-framework (based on Werkzeug ) which uses Python (2.6 in my case).
...
Force LF eol in git repo and working copy
...y hosted on github. Many of the files were initially developed on Windows, and I wasn't too careful about line endings. When I performed the initial commit, I also didn't have any git configuration in place to enforce correct line endings. The upshot is that I have a number of files with CRLF line e...
Express.js: how to get remote client address
I don't completely understand how I should get a remote user IP address.
16 Answers
16...
C# operator overload for `+=`?
... think this is because there will be an effect for the Garbage collection and memory management, which is a potential security hole in CLR strong typed world.
Nevertheless, let's see what exactly an operator is. According to the famous Jeffrey Richter's book, each programming language has its own ...