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Sorting list based on values from another list?
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good solution! But it should be: The list is ordered regarding the first element of the pairs, and the comprehension extracts the 'second' element of the pairs.
– MasterControlProgram
Oct 6 '17 at 14:31
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Check if all elements in a list are identical
...ution which optimizes away calls to obj.__eq__ when lhs is rhs, and out-of-order optimizations to allow short circuiting sorted lists more quickly.
– Glenn Maynard
Oct 2 '10 at 8:31
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Convert a String In C++ To Upper Case
...ng slow on Windows when a locale is set.
I was shocked that Boost is an order of magnitude slower than the other options. I double-checked that I had -O3 enabled, and even single-stepped the asm to see what it was doing. It's almost exactly the same speed with clang++ 3.8. It has huge overhead...
I can’t find the Android keytool
... Linux users have an easier time with this so I won't address them.
So in order to use mapviews in your Android apps, Google wants to check in with them so you can sign off on an Android Maps APIs Terms Of Service agreement. I think they don't want you to make any turn-by-turn GPS apps to compete w...
What's the $unwind operator in MongoDB?
...g and obtaining the data from your storage locations.
That being said, in order to understand the concept behind the $unwind parameter, you first must understand what the use case that you are trying to quote is saying. The example document from mongodb.org is as follows:
{
title : "this is my ti...
Cannot create an NSPersistentStoreCoordinator with a nil model
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Instead of deleting it you may eventually edit it in order to change the filename stored to the latest version of youl xcdatamodel
– furins
Jun 24 '14 at 17:18
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data.table vs dplyr: can one do something well the other can't or does poorly?
...ese aspects to provide a comprehensive answer/comparison (in no particular order of importance): Speed, Memory usage, Syntax and Features.
My intent is to cover each one of these as clearly as possible from data.table perspective.
Note: unless explicitly mentioned otherwise, by referring to dpl...
Block Comments in a Shell Script
...he above code would result in:
This is outside the commented block
In order to uncomment the code blocks thus commented, say
alias BEGINCOMMENT="if : ; then"
instead of
alias BEGINCOMMENT="if [ ]; then"
in the example above.
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Is Java “pass-by-reference” or “pass-by-value”?
...e get to the Java implementation:
Values go on and off the stack in a nice orderly fashion, like a stack of plates at a cafeteria.
Memory in the heap (also known as dynamic memory) is haphazard and disorganized. The JVM just finds space wherever it can, and frees it up as the variables that use it a...
Sleep until a specific time/date
...X and don't work under MacOS! If under Mac, goto my pure bash function)
In order to reduce forks, instead of running date two times, I prefer to use this:
Simple starting sample
sleep $(($(date -f - +%s- <<< $'tomorrow 21:30\nnow')0))
where tomorrow 21:30 could be replaced by any kind of d...