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How to randomize (or permute) a dataframe rowwise and columnwise?
...,]
> df2
a b c
3 0 1 0
4 0 0 0
2 1 0 0
1 1 1 0
By default sample() randomly reorders the elements passed as the first argument. This means that the default size is the size of the passed array. Passing parameter replace=FALSE (the default) to sample(...) ensures that sampling is done withou...
Why does Lua have no “continue” statement?
I have been dealing a lot with Lua in the past few months, and I really like most of the features but I'm still missing something among those:
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Why does this Java program terminate despite that apparently it shouldn't (and didn't)?
...etely wrong. An actuator on an electron microscope went over its boundary, and after a chain of events I lost $12 million of equipment. I've narrowed down over 40K lines in the faulty module to this:
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Difference between float and decimal data type
What difference does it make when I use float and decimal data types in MySQL?.
12 Answers
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Equation (expression) parser with precedence?
...'ve developed an equation parser using a simple stack algorithm that will handle binary (+, -, |, &, *, /, etc) operators, unary (!) operators, and parenthesis.
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TortoiseSVN icons not showing up under Windows 7
I can't seem to get the icons to display under Windows 7 and I really miss this from Windows XP.
31 Answers
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What exactly is a C pointer if not a memory address?
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The C standard does not define what a pointer is internally and how it works internally. This is intentional so as not to limit the number of platforms, where C can be implemented as a compiled or interpreted language.
A pointer val...
Android requires compiler compliance level 5.0 or 6.0. Found '1.7' instead. Please use Android Tools
Did anybody have similar problem with this, I import android project and I get
errors like
12 Answers
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What should main() return in C and C++?
...t is the correct (most efficient) way to define the main() function in C and C++ — int main() or void main() — and why? And how about the arguments?
If int main() then return 1 or return 0 ?
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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...