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Convert column classes in data.table
... dt[, Quarter:=as.character(Quarter)]
str(dtnew)
Classes ‘data.table’ and 'data.frame': 10 obs. of 3 variables:
$ ID : Factor w/ 2 levels "A","B": 1 1 1 1 1 2 2 2 2 2
$ Quarter: chr "1" "2" "3" "4" ...
$ value : num -0.838 0.146 -1.059 -1.197 0.282 ...
Using lapply and as.charac...
What SOAP client libraries exist for Python, and where is the documentation for them? [closed]
I've never used SOAP before and I'm sort of new to Python. I'm doing this to get myself acquainted with both technologies. I've installed SOAPlib and I've tried to read their Client documentation, but I don't understand it too well. Is there anything else I can look into which is more suite...
Quick easy way to migrate SQLite3 to MySQL? [closed]
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Everyone seems to starts off with a few greps and perl expressions and you sorta kinda get something that works for your particular dataset but you have no idea if it's imported the data correctly or not. I'm seriously surprised nobody's built a solid library that can co...
Safest way to convert float to integer in python?
Python's math module contain handy functions like floor & ceil . These functions take a floating point number and return the nearest integer below or above it. However these functions return the answer as a floating point number. For example:
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Remove everything after a certain character
...hoose everything up to that character? I'm getting the value from an href and up to the "?", and it's always going to be a different amount of characters.
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Why switch is faster than if
...ave a check, a jump to the next clause, a check, a jump to the next clause and so on. With switch the JVM loads the value to compare and iterates through the value table to find a match, which is faster in most cases.
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How to design a multi-user ajax web application to be concurrently safe
...ges to objects while at the same time being able to deliver updates timely and efficiently, detecting and resolving conflicts like the one above.
If I was in your shoes I would develop something like this:
1. Server-Side:
Determine a reasonable level at which you would define what I'd call "atom...
How to redirect cin and cout to files?
How can I redirect cin to in.txt and cout to out.txt ?
5 Answers
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How do I convert an enum to a list in C#? [duplicate]
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that's superfluous, and will mean extra copying. Enum.GetValues returns an array already, so you just have to do var values = (SomeEnum[])Enum.GetValues(typeof(SomeEnum))
– thecoop
Nov 9 '10 at 2:33
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Format date and time in a Windows batch script
In a Windows (Windows XP) batch script I need to format the current date and time for later use in files names, etc.
33 An...