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Is there a MySQL option/feature to track history of changes to records?
...QL database. So when a field has been changed, the old vs new is available and the date this took place. Is there a feature or common technique to do this?
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What is the scope of variables in JavaScript?
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TLDR
JavaScript has lexical (also called static) scoping and closures. This means you can tell the scope of an identifier by looking at the source code.
The four scopes are:
Global - visible by everything
Function - visible within a function (and its sub-functions and blocks)
Bloc...
What's the difference between lapply and do.call?
I'm learning R recently and confused by two function: lapply and do.call . It seems that they're just similar to map function in Lisp. But why are there two functions with such a different name? Why doesn't R just use a function called map ?
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Remap values in pandas column with a dict
... edited Oct 3 '18 at 8:31
Winand
1,2631717 silver badges3535 bronze badges
answered Nov 27 '13 at 19:06
DSM...
Good example of livelock?
I understand what livelock is, but I was wondering if anyone had a good code-based example of it? And by code-based, I do not mean "two people trying to get past each other in a corridor". If I read that again, I'll lose my lunch.
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What is the difference between procedural programming and functional programming? [closed]
I've read the Wikipedia articles for both procedural programming and functional programming , but I'm still slightly confused. Could someone boil it down to the core?
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Why does changing the sum order returns a different result?
...gnificant digits, where each addition is performed at "infinite" precision and then rounded to the nearest representable number. Here are two sums:
1/3 + 2/3 + 2/3 = (0.3333 + 0.6667) + 0.6667
= 1.000 + 0.6667 (no rounding needed!)
= 1.667 (where 1.6667 is rounded to...
Regex Pattern to Match, Excluding when… / Except between
...ome useful ideas but I want something more complete that I can 100% understand and reuse; that's why I set a bounty. Also ideas that work everywhere are better for me than not standard syntax like \K
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Best way to iterate through a Perl array
Which is the best implementation(in terms of speed and memory usage) for iterating through a Perl array? Is there any better way? ( @Array need not be retained).
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How to assign from a function which returns more than one value?
...ge. It does not require a special operator but does require that the left hand side be written using list[...] like this:
library(gsubfn) # need 0.7-0 or later
list[a, b] <- functionReturningTwoValues()
If you only need the first or second component these all work too:
list[a] <- function...