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Speed up the loop operation in R
....time(dayloop2(X))
Result is
You can see that your version depends exponentially from nrow(X). Modified version has linear relation, and simple lm model predict that for 850,000 rows computation takes 6 minutes and 10 seconds.
Power of vectorization
As Shane and Calimo states in theirs answer...
What are .dex files in Android?
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About the .dex File :
One of the most remarkable features of the Dalvik Virtual Machine (the workhorse under the Android system) is that it does not use Java bytecode. Instead, a homegrown format called DEX was introduced and not even the bytecode...
How do you log all events fired by an element in jQuery?
...no way to display custom events, for example if a plugin fires some custom ones?
– Daniel T.
Sep 16 '11 at 2:46
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SQL Server Profiler - How to filter trace to only display events from one database?
...filer 2000 is used with database residing in SQLServer 2000 - problem mentioned problem persists, but when SQL Profiler 2005 is used with SQLServer 2005 database, it works perfect!
In Summary, the issue seems to be prevalent in SQLServer 2000 & rectified in SQLServer 2005.
The solution for the...
Windows shell command to get the full path to the current directory?
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Honestly, I couldn't think of anything else they might be trying to ask as the question stated.
– Trevor Bramble
Mar 3 '09 at 19:11
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What are database normal forms and can you give examples? [closed]
...is the most basic of normal forms - each cell in a table must contain only one piece of information, and there can be no duplicate rows.
2NF and 3NF are all about being dependent on the primary key. Recall that a primary key can be made up of multiple columns. As Chris said in his response:
The da...
Should I initialize variable within constructor or outside constructor [duplicate]
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I find the second style (declaration + initialization in one go) superior. Reasons:
It makes it clear at a glance how the variable is initialized. Typically, when reading a program and coming across a variable, you'll first go to its declaration (often automatic in IDEs). With st...
Swift compiler segmentation fault when building
... Swift has been giving me unpleasant surprises all along the way, but this one is way over the limit.
– CodeBrew
Feb 15 '15 at 22:37
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Get Substring between two characters using javascript
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Does anyone know how I would do this for every occurence of a substring between my starting and ending string?
– MarksCode
Feb 26 '16 at 5:11
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Why is @autoreleasepool still needed with ARC?
...et rid of retains, releases and autoreleases, it just adds in the required ones for you. So there are still calls to retain, there are still calls to release, there are still calls to autorelease and there are still auto release pools.
One of the other changes they made with the new Clang 3.0 compi...