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Why does Java's hashCode() in String use 31 as a multiplier?
... subtract instruction. However, if your multiplier is slow this is still a win. Modern processors tend to have fast multipliers so it doesn't make much difference, so long as 32 goes on the correct side.
It's not a great hash algorithm, but it's good enough and better than the 1.0 code (and very mu...
How to get a vertical geom_vline to an x-axis of class date?
...
on my machine (Win10 with R 3.2.2 and ggplot 1.0.1), I have to coerce the date to POSIXct to get it to align properly: as.POSIXct(as.Date(c("2016-12-01","2017-02-01")))
– Jthorpe
Jul 28 '17 at 17:36
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PhpStorm wrap/surround selection?
...ng (word, condition) and press Cmd + Alt + T (on Mac) , Ctrl + Alt + T (on Windows). Available Surround With options dialog box will be displayed.
Update (for PhpStorm8)
For PhpStorm Version 8, tick on checkbox of Preferences -> Editor -> General -> Smart Keys -> Surround selection on ...
Persistent invalid graphics state error when using ggplot2
...iously. Take the below console output for example. The figure margins (the window that displays your plots) were too small to display the pairs(MinusInner) plot. Then when I tried to make the next qplot, R was still hung up on previous error.
pairs(MinusInner)
Error in plot.new() : figure mar...
How can I get the current network interface throughput statistics on Linux/UNIX? [closed]
...ning to parse tcpdump output again. Thank you iftop and wireshark, for allowing me to be this lazy.
– Parthian Shot
Aug 4 '14 at 20:21
1
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How to change max_allowed_packet size
...k some would also want to know how to find the my.ini file on your PC. For windows users, I think the best way is as follows:
Win+R(shortcut for 'run'), type services.msc, Enter
You could find an entry like 'MySQL56', right click on it, select properties
You could see sth like "D:/Program Files/My...
Why is there no tuple comprehension in Python?
...es return a callable so if I only need to do it once I don't see much of a win vs just using tuple(obj[item] for item in items) directly. In my case I was embedding this into a list comprehension to make a list of tuple records. If I need to do this repeatedly throughout the code then itemgetter l...
Artificially create a connection timeout error
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The following URL always gives a timeout, and combines the best of @Alexander and @Emu's answers above:
http://example.com:81
Using example.com:81 is an improvement on Alexander's answer because example.com is reserved by the DNS st...
Programmer Puzzle: Encoding a chess board state throughout a game
...s “all subsequent legal moves”. The problem also says nothing about knowing the moves up to this point. That’s actually a problem as I’ll explain.
Castling
The game has proceeded as follows:
e4 e5
Nf3 Nc6
Bb5 a6
Ba4 Bc5
The board looks as follows:
White has the option of castling...
Performance - Date.now() vs Date.getTime()
...to Date's methods without re-instantiating. In that case, Date.now() still wins over new Date() or the like, though only by about 20% on my Chrome and by a tiny amount on IE.
See my JSPERF on
timeStamp2.setTime(Date.now()); // set to current;
vs.
timeStamp1 = new Date(); // set to current;
ht...