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Static variables in member functions
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Since class A is a non-template class and A::foo() is a non-template function. There will be only one copy of static int i inside the program.
Any instance of A object will affect the same i and lifetime of i will remain through out the program. To add an exampl...
Which is better, number(x) or parseFloat(x)?
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The difference between parseFloat and Number
parseFloat/parseInt is for parsing a string, while Number/+ is for coercing a value to a number. They behave differently. But first let's look at where they behave the same:
parseFloat('3'); // => 3
Number('3'...
Difference between '..' (double-dot) and '…' (triple-dot) in range generation?
I've just started learning Ruby and Ruby on Rails and came across validation code that uses ranges:
5 Answers
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Exception messages in English?
...Message to a file. However, they are written in the culture of the client. And Turkish errors don't mean a lot to me.
16 An...
html5 - canvas element - Multiple layers
...ver, you could layer multiple <canvas> elements on top of each other and accomplish something similar.
<div style="position: relative;">
<canvas id="layer1" width="100" height="100"
style="position: absolute; left: 0; top: 0; z-index: 0;"></canvas>
<canvas id="layer...
How to optimize for-comprehensions and loops in Scala?
...imizer can eliminate the foreach but cannot yet eliminate the throw/catch. And throw/catch is expensive. But since such nested returns are rare in Scala programs, the optimizer did not yet address this case. There is work going on to improve the optimizer which hopefully will solve this issue soon.
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Why does parseInt(1/0, 19) return 18?
...parseInt scans the input "Infinity" to find which part of it can be parsed and stops after accepting the first I (because n is not a valid digit in base 19).
Therefore it behaves as if you called parseInt("I", 19), which converts to decimal 18 by the table above.
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Programmatically generate video or animated GIF in Python?
...d not using images2gif from visvis because it has problems with PIL/Pillow and is not actively maintained (I should know, because I am the author).
Instead, please use imageio, which was developed to solve this problem and more, and is intended to stay.
Quick and dirty solution:
import imageio
im...
Design patterns or best practices for shell scripts [closed]
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I wrote quite complex shell scripts and my first suggestion is "don't". The reason is that is fairly easy to make a small mistake that hinders your script, or even make it dangerous.
That said, I don't have other resources to pass you but my personal experienc...
Convert a list of data frames into one data frame
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since it's 2018 and dplyr is both fast and a solid tool to use, I've changed this to the accepted answer. The years, they fly by!
– JD Long
Jan 12 '19 at 12:03
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