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Compare two data.frames to find the rows in data.frame 1 that are not present in data.frame 2
...<- data.frame(a = 1:3, b = letters[1:3])
comparison <- compare(a1,a2,allowAll=TRUE)
comparison$tM
# a b
#1 1 a
#2 2 b
#3 3 c
The function compare gives you a lot of flexibility in terms of what kind of comparisons are allowed (e.g. changing order of elements of each vector, changing order a...
How to use npm with node.exe?
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The current windows installer from nodejs.org as of v0.6.11 (2012-02-20) will install NPM along with NodeJS.
NOTES:
At this point, the 64-bit version is your best bet
The install path for 32-bit node is "Program Files (x86)" in 64-bit windows.
Y...
What's the best name for a non-mutating “add” method on an immutable collection?
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In situations like that, I usually go with Concat. That usually implies to me that a new object is being created.
var p = listA.Concat(listB);
var k = listA.Concat(item);
share...
SET versus SELECT when assigning variables?
...ed then SET will assign NULL, where SELECT will not make the assignment at all (so the variable will not be changed from its previous value)
As far as speed differences - there are no direct differences between SET and SELECT. However SELECT's ability to make multiple assignments in one shot does ...
Action Image MVC3 Razor
...butes = HtmlHelper.AnonymousObjectToHtmlAttributes(htmlAttributes); and finally foreach (var attr in attributes){ imgBuilder.MergeAttribute(attr.Key, attr.Value.ToString());}
– guzart
Dec 4 '11 at 5:33
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How to tell which version of a gem a rails app is using
...gating a rails app - the prod server has two version of a specific gem installed, how can I tell which version the prod app is using?
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How to grep and replace
I need to recursively search for a specified string within all files and subdirectories within a directory and replace this string with another string.
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Does name length impact performance in Redis?
I like to use verbose names in Redis, for instance set-allBooksBelongToUser:$userId .
4 Answers
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Why is debugging better in an IDE? [closed]
...hat an IDE debugger will give you over trace messages in code:
View the call stack at any point in time, giving you a context for your current stack frame.
Step into libraries that you are not able to re-compile for the purposes of adding traces (assuming you have access to the debug symbols)
Chan...
Arrays, heap and stack and value types
...parts of the program and it'd clutter up the stack if they were left on it all the time. Or am I wrong? I'd guess they'd just be boxed and would live on the heap for as long the array existed.
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