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Extract a substring according to a pattern
...regex
If the colon were not always in a known position we could modify (4) by searching for it:
substring(string, regexpr(":", string) + 1)
5) strapplyc
strapplyc returns the parenthesized portion:
library(gsubfn)
strapplyc(string, ":(.*)", simplify = TRUE)
## [1] "E001" "E002" "E003"
6) read.dcf
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How to compute the sum and average of elements in an array?
... @zamnuts I'm with you, I think Thor84no comment's totally out of order - I'd be happy to be fired from a place which finds array.reduce too complex. However I wouldn't use your code either, for the simple fact it has a division and two extra additions at ever step, which is never going to ...
STAThread and multithreading
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Entity Framework - Include Multiple Levels of Properties
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@Adeem you need to call Include for each property: Db.States.Include(state => state.Cities.Select(city => city.Customers).Include(state => state.Cities.Select(city => city.Vendors)
– Diego Torres
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Knight's Shortest Path on Chessboard
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You have a graph here, where all available moves are connected (value=1), and unavailable moves are disconnected (value=0), the sparse matrix would be like:
(a1,b3)=1,
(a1,c2)=1,
.....
And the shortest path of two points in a graph can be found usin...
How do I determine file encoding in OS X?
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That's a function call you would use if you want to write a program. From the command line, just type ls -l@ <filename> to see what attributes are set for the file. To see the actual attribute, type xattr -p com.apple.TextEncoding <fil...
What Computer Science concepts should I know? [closed]
...s, but find wikipedia too academic :D
Anyway, here goes, in no particular order:
The relational model: Introduction to Database systems
Object orientation : Object Thinking
Complexity and computation theory (think Turing machines and automata): Introduction to theory of computation
A little compi...
Android: Access child views from a ListView
...ses, but I don't understand why you believe that child views appear in the order they are in the array of child views. Since views can be reused how can we be sure that first view doesn't represent the last visible view?
– Victor Denisov
Oct 28 '13 at 10:01
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Advantage of switch over if-else statement
... the average case) or simply build a jump-table (works without compares at all).
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What is the recommended way to delete a large number of items from DynamoDB?
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What I ideally want to do is call LogTable.DeleteItem(user_id) -
Without supplying the range, and have it delete everything for me.
An understandable request indeed; I can imagine advanced operations like these might get added over...