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Objective-C Split()?
... strings in objective c into arrays? I mean like this - input string Yes:0:42:value into an array of (Yes,0,42,value)?
5 An...
Warning as error - How to rid these
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answered Mar 26 '10 at 2:43
Michael PetrottaMichael Petrotta
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Difference between a Factory, Provider and a Service?
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174
Factory: Assembles classes, either by composing a bunch of bits together, or choosing type based...
how to get program files x86 env variable?
...he location of Program Files (x86) in command prompt. I'm using Windows 7 64bit.
4 Answers
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Reading header data in Ruby on Rails
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149
request.headers["Content-Type"] # => "text/plain"
replace "Content-Type" with the name of ...
How do I make a matrix from a list of vectors in R?
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124
One option is to use do.call():
> do.call(rbind, a)
[,1] [,2] [,3] [,4] [,5] [,6]
[...
What does dot (.) mean in a struct initializer?
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4 Answers
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Active
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Assign multiple columns using := in data.table, by group
...b col1 col2
# 1: 1 1 hi hello
# 2: 2 2 hi hello
# 3: 3 3 hi hello
# 4: 1 4 hi hello
# 5: 2 5 hi hello
# 6: 3 6 hi hello
x[ , c("mean", "sum") := list(mean(b), sum(b)), by = a][]
# a b col1 col2 mean sum
# 1: 1 1 hi hello 2.5 5
# 2: 2 2 hi hello 3.5 7
# 3: 3 3 hi hello ...
What does “Receiver type 'CALayer' for instance message is a forward declaration” mean here?
I'm porting a block of code from an iOS4 project to iOS5 and I'm having some troubles with ARC. The code generates a PDF from a screen capture.
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C#/Linq: Apply a mapping function to each element in an IEnumerable?
...ethod:
IEnumerable<int> integers = new List<int>() { 1, 2, 3, 4, 5 };
IEnumerable<string> strings = integers.Select(i => i.ToString());
Or in LINQ syntax:
IEnumerable<int> integers = new List<int>() { 1, 2, 3, 4, 5 };
var strings = from i in integers
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