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Is ASCII code 7-bit or 8-bit?
...he 8th bit of each byte of text for its own purposes ("not 8-bit clean"). Nowadays people think of it as an 8-bit coding in which bytes 0x80 through 0xFF have no defined meaning, but that's a retcon.
There are dozens of text encodings that make use of the 8th bit; they can be classified as ASCII-c...
How do I efficiently iterate over each entry in a Java Map?
...
To summarize the other answers and combine them with what I know, I found 10 main ways to do this (see below). Also, I wrote some performance tests (see results below). For example, if we want to find the sum of all of the keys and values of a map, we can write:
Using iterator and Ma...
How to git-cherry-pick only changes to certain files?
...tively with git reset -p HEAD. It's the equivalent of add -p but very few know that it exists.
– Patrick Schlüter
Mar 14 '17 at 9:09
2
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Are there any suggestions for developing a C# coding standards / best practices document? [closed]
...nd it is authored by Juval Lowy
C# Coding Standard
NB: the above link is now dead. To get the .zip file you need to give them your email address (but they won't use it for marketing... honestly) Try here
share
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Why Choose Struct Over Class?
...ruct version took 0.010532942s (900 times faster)
OLD RESULTS (from unknown time)
(Ran on struct/class with 1 field, not 10)
With release build on my MacBook Pro:
The class version took 1.10082 sec
The struct version took 0.02324 sec (50 times faster)
...
What does $_ mean in PowerShell?
...erty -Name Bar -Value $_.Name -PassThru | Select Bar ... Well, it can work if you have a $_ in the scope where you're executing that pipeline. But that's very different from what you usually mean when trying to write something like that.
– Joey
Nov 6 '15 at 17:...
How to validate IP address in Python? [duplicate]
... representations of IP addresses.
If you're using Python 3.3 or later, it now includes the ipaddress module:
>>> import ipaddress
>>> ipaddress.ip_address('127.0.0.1')
IPv4Address('127.0.0.1')
>>> ipaddress.ip_address('277.0.0.1')
Traceback (most recent call last):
Fil...
Understanding ibeacon distancing
...ssi) over the calibrated transmitter power (txPower). The txPower is the known measured signal strength in rssi at 1 meter away. Each beacon must be calibrated with this txPower value to allow accurate distance estimates.
While the distance estimates are useful, they are not perfect, and require ...
Get ffmpeg information in friendly way
...
Now is possible to use -progress - to print friendly info formatted by key=value.
ffmpeg -i video.mp4 .......-s 1920x1080 -progress - -y out.mp4
speed=5.75x
frame=697
fps=167.7
stream_0_0_q=39.0
bitrate=2337.0kbits/s
total...
Principal component analysis in Python
...o 90 %, 95 % ...
p.npc: number of principal components,
e.g. 2 if the top 2 eigenvalues are >= `fraction` of the total.
It's ok to change this; methods use the current value.
Methods:
The methods of class PCA transform vectors or arrays of e.g.
20 variables, 2 princip...